diff --git a/package-lock.json b/package-lock.json
index 89de517..4961875 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -2682,6 +2682,17 @@
         "json-stable-stringify": "^1.0.1",
         "rsvp": "^4.8.4",
         "workerpool": "^3.1.1"
+      },
+      "dependencies": {
+        "broccoli-merge-trees": {
+          "version": "3.0.2",
+          "resolved": "https://registry.npmjs.org/broccoli-merge-trees/-/broccoli-merge-trees-3.0.2.tgz",
+          "integrity": "sha512-ZyPAwrOdlCddduFbsMyyFzJUrvW6b04pMvDiAQZrCwghlvgowJDY+EfoXn+eR1RRA5nmGHJ+B68T63VnpRiT1A==",
+          "requires": {
+            "broccoli-plugin": "^1.3.0",
+            "merge-trees": "^2.0.0"
+          }
+        }
       }
     },
     "broccoli-builder": {
@@ -2940,12 +2951,28 @@
       }
     },
     "broccoli-merge-trees": {
-      "version": "3.0.2",
-      "resolved": "https://registry.npmjs.org/broccoli-merge-trees/-/broccoli-merge-trees-3.0.2.tgz",
-      "integrity": "sha512-ZyPAwrOdlCddduFbsMyyFzJUrvW6b04pMvDiAQZrCwghlvgowJDY+EfoXn+eR1RRA5nmGHJ+B68T63VnpRiT1A==",
+      "version": "4.1.0",
+      "resolved": "https://registry.npmjs.org/broccoli-merge-trees/-/broccoli-merge-trees-4.1.0.tgz",
+      "integrity": "sha512-1OXsksKPFiRdiZZOfh1z1mm7ZqKezlMS+DPBpHMDLSb6AhYHvoQfjf0KuMXbY8aoYskj7+Z+EJ5SsS/OC2v5yw==",
       "requires": {
-        "broccoli-plugin": "^1.3.0",
+        "broccoli-plugin": "^3.1.0",
         "merge-trees": "^2.0.0"
+      },
+      "dependencies": {
+        "broccoli-plugin": {
+          "version": "3.1.0",
+          "resolved": "https://registry.npmjs.org/broccoli-plugin/-/broccoli-plugin-3.1.0.tgz",
+          "integrity": "sha512-7w7FP8WJYjLvb0eaw27LO678TGGaom++49O1VYIuzjhXjK5kn2+AMlDm7CaUFw4F7CLGoVQeZ84d8gICMJa4lA==",
+          "requires": {
+            "broccoli-node-api": "^1.6.0",
+            "broccoli-output-wrapper": "^2.0.0",
+            "fs-merger": "^3.0.1",
+            "promise-map-series": "^0.2.1",
+            "quick-temp": "^0.1.3",
+            "rimraf": "^2.3.4",
+            "symlink-or-copy": "^1.1.8"
+          }
+        }
       }
     },
     "broccoli-middleware": {
@@ -3007,8 +3034,15 @@
     "broccoli-node-info": {
       "version": "2.1.0",
       "resolved": "https://registry.npmjs.org/broccoli-node-info/-/broccoli-node-info-2.1.0.tgz",
-      "integrity": "sha512-l6qDuboJThHfRVVWQVaTs++bFdrFTP0gJXgsWenczc1PavRVUmL1Eyb2swTAXXMpDOnr2zhNOBLx4w9AxkqbPQ==",
-      "dev": true
+      "integrity": "sha512-l6qDuboJThHfRVVWQVaTs++bFdrFTP0gJXgsWenczc1PavRVUmL1Eyb2swTAXXMpDOnr2zhNOBLx4w9AxkqbPQ=="
+    },
+    "broccoli-output-wrapper": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/broccoli-output-wrapper/-/broccoli-output-wrapper-2.0.0.tgz",
+      "integrity": "sha512-V/ozejo+snzNf75i/a6iTmp71k+rlvqjE3+jYfimuMwR1tjNNRdtfno+NGNQB2An9bIAeqZnKhMDurAznHAdtA==",
+      "requires": {
+        "heimdalljs-logger": "^0.1.10"
+      }
     },
     "broccoli-persistent-filter": {
       "version": "2.3.1",
@@ -3169,6 +3203,30 @@
         "walk-sync": "^1.1.3"
       },
       "dependencies": {
+        "broccoli-merge-trees": {
+          "version": "3.0.2",
+          "resolved": "https://registry.npmjs.org/broccoli-merge-trees/-/broccoli-merge-trees-3.0.2.tgz",
+          "integrity": "sha512-ZyPAwrOdlCddduFbsMyyFzJUrvW6b04pMvDiAQZrCwghlvgowJDY+EfoXn+eR1RRA5nmGHJ+B68T63VnpRiT1A==",
+          "dev": true,
+          "requires": {
+            "broccoli-plugin": "^1.3.0",
+            "merge-trees": "^2.0.0"
+          },
+          "dependencies": {
+            "broccoli-plugin": {
+              "version": "1.3.1",
+              "resolved": "https://registry.npmjs.org/broccoli-plugin/-/broccoli-plugin-1.3.1.tgz",
+              "integrity": "sha512-DW8XASZkmorp+q7J4EeDEZz+LoyKLAd2XZULXyD9l4m9/hAKV3vjHmB1kiUshcWAYMgTP1m2i4NnqCE/23h6AQ==",
+              "dev": true,
+              "requires": {
+                "promise-map-series": "^0.2.1",
+                "quick-temp": "^0.1.3",
+                "rimraf": "^2.3.4",
+                "symlink-or-copy": "^1.1.8"
+              }
+            }
+          }
+        },
         "broccoli-plugin": {
           "version": "2.1.0",
           "resolved": "https://registry.npmjs.org/broccoli-plugin/-/broccoli-plugin-2.1.0.tgz",
@@ -4377,6 +4435,16 @@
         "yam": "^1.0.0"
       },
       "dependencies": {
+        "broccoli-merge-trees": {
+          "version": "3.0.2",
+          "resolved": "https://registry.npmjs.org/broccoli-merge-trees/-/broccoli-merge-trees-3.0.2.tgz",
+          "integrity": "sha512-ZyPAwrOdlCddduFbsMyyFzJUrvW6b04pMvDiAQZrCwghlvgowJDY+EfoXn+eR1RRA5nmGHJ+B68T63VnpRiT1A==",
+          "dev": true,
+          "requires": {
+            "broccoli-plugin": "^1.3.0",
+            "merge-trees": "^2.0.0"
+          }
+        },
         "broccoli-source": {
           "version": "3.0.0",
           "resolved": "https://registry.npmjs.org/broccoli-source/-/broccoli-source-3.0.0.tgz",
@@ -5505,6 +5573,18 @@
         "ember-cli-babel": "^7.8.0",
         "ember-cli-test-loader": "^2.2.0",
         "qunit": "^2.9.2"
+      },
+      "dependencies": {
+        "broccoli-merge-trees": {
+          "version": "3.0.2",
+          "resolved": "https://registry.npmjs.org/broccoli-merge-trees/-/broccoli-merge-trees-3.0.2.tgz",
+          "integrity": "sha512-ZyPAwrOdlCddduFbsMyyFzJUrvW6b04pMvDiAQZrCwghlvgowJDY+EfoXn+eR1RRA5nmGHJ+B68T63VnpRiT1A==",
+          "dev": true,
+          "requires": {
+            "broccoli-plugin": "^1.3.0",
+            "merge-trees": "^2.0.0"
+          }
+        }
       }
     },
     "ember-resolver": {
@@ -5570,6 +5650,28 @@
             }
           }
         },
+        "broccoli-merge-trees": {
+          "version": "3.0.2",
+          "resolved": "https://registry.npmjs.org/broccoli-merge-trees/-/broccoli-merge-trees-3.0.2.tgz",
+          "integrity": "sha512-ZyPAwrOdlCddduFbsMyyFzJUrvW6b04pMvDiAQZrCwghlvgowJDY+EfoXn+eR1RRA5nmGHJ+B68T63VnpRiT1A==",
+          "dev": true,
+          "requires": {
+            "broccoli-plugin": "^1.3.0",
+            "merge-trees": "^2.0.0"
+          },
+          "dependencies": {
+            "merge-trees": {
+              "version": "2.0.0",
+              "resolved": "https://registry.npmjs.org/merge-trees/-/merge-trees-2.0.0.tgz",
+              "integrity": "sha512-5xBbmqYBalWqmhYm51XlohhkmVOua3VAUrrWh8t9iOkaLpS6ifqm/UVuUjQCeDVJ9Vx3g2l6ihfkbLSTeKsHbw==",
+              "dev": true,
+              "requires": {
+                "fs-updater": "^1.0.4",
+                "heimdalljs": "^0.2.5"
+              }
+            }
+          }
+        },
         "broccoli-persistent-filter": {
           "version": "1.4.6",
           "resolved": "https://registry.npmjs.org/broccoli-persistent-filter/-/broccoli-persistent-filter-1.4.6.tgz",
@@ -5722,6 +5824,16 @@
         "silent-error": "^1.1.1"
       },
       "dependencies": {
+        "broccoli-merge-trees": {
+          "version": "3.0.2",
+          "resolved": "https://registry.npmjs.org/broccoli-merge-trees/-/broccoli-merge-trees-3.0.2.tgz",
+          "integrity": "sha512-ZyPAwrOdlCddduFbsMyyFzJUrvW6b04pMvDiAQZrCwghlvgowJDY+EfoXn+eR1RRA5nmGHJ+B68T63VnpRiT1A==",
+          "dev": true,
+          "requires": {
+            "broccoli-plugin": "^1.3.0",
+            "merge-trees": "^2.0.0"
+          }
+        },
         "ember-cli-version-checker": {
           "version": "3.1.3",
           "resolved": "https://registry.npmjs.org/ember-cli-version-checker/-/ember-cli-version-checker-3.1.3.tgz",
@@ -6910,13 +7022,58 @@
       "version": "8.1.0",
       "resolved": "https://registry.npmjs.org/fs-extra/-/fs-extra-8.1.0.tgz",
       "integrity": "sha512-yhlQgA6mnOJUKOsRUFsgJdQCvkKhcz8tlZG5HBQfReYZy46OwLcY+Zia0mtdHsOo9y/hP+CxMN0TU9QxoOtG4g==",
-      "dev": true,
       "requires": {
         "graceful-fs": "^4.2.0",
         "jsonfile": "^4.0.0",
         "universalify": "^0.1.0"
       }
     },
+    "fs-merger": {
+      "version": "3.0.2",
+      "resolved": "https://registry.npmjs.org/fs-merger/-/fs-merger-3.0.2.tgz",
+      "integrity": "sha512-63wmgjPDClP5XcTSKdIXz66X5paYy/m2Ymq5c5YpGxRQEk1HFZ8rtti3LMNSOSw1ketbBMGbSFFcQeEnpnzDpQ==",
+      "requires": {
+        "broccoli-node-api": "^1.7.0",
+        "broccoli-node-info": "^2.1.0",
+        "fs-extra": "^8.0.1",
+        "fs-tree-diff": "^2.0.1",
+        "rimraf": "^2.6.3",
+        "walk-sync": "^2.0.2"
+      },
+      "dependencies": {
+        "fs-tree-diff": {
+          "version": "2.0.1",
+          "resolved": "https://registry.npmjs.org/fs-tree-diff/-/fs-tree-diff-2.0.1.tgz",
+          "integrity": "sha512-x+CfAZ/lJHQqwlD64pYM5QxWjzWhSjroaVsr8PW831zOApL55qPibed0c+xebaLWVr2BnHFoHdrwOv8pzt8R5A==",
+          "requires": {
+            "@types/symlink-or-copy": "^1.2.0",
+            "heimdalljs-logger": "^0.1.7",
+            "object-assign": "^4.1.0",
+            "path-posix": "^1.0.0",
+            "symlink-or-copy": "^1.1.8"
+          }
+        },
+        "matcher-collection": {
+          "version": "2.0.1",
+          "resolved": "https://registry.npmjs.org/matcher-collection/-/matcher-collection-2.0.1.tgz",
+          "integrity": "sha512-daE62nS2ZQsDg9raM0IlZzLmI2u+7ZapXBwdoeBUKAYERPDDIc0qNqA8E0Rp2D+gspKR7BgIFP52GeujaGXWeQ==",
+          "requires": {
+            "@types/minimatch": "^3.0.3",
+            "minimatch": "^3.0.2"
+          }
+        },
+        "walk-sync": {
+          "version": "2.0.2",
+          "resolved": "https://registry.npmjs.org/walk-sync/-/walk-sync-2.0.2.tgz",
+          "integrity": "sha512-dCZkrxfHjPn7tIvdYrX3uMD/R0beVrHpA8lROQ5wWrl8psJgR6xwCkwqTFes0dNujbS2o/ITpvSYgIFsLsf13A==",
+          "requires": {
+            "@types/minimatch": "^3.0.3",
+            "ensure-posix-path": "^1.1.0",
+            "matcher-collection": "^2.0.0"
+          }
+        }
+      }
+    },
     "fs-minipass": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/fs-minipass/-/fs-minipass-2.0.0.tgz",
@@ -7273,8 +7430,7 @@
     "graceful-fs": {
       "version": "4.2.2",
       "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.2.2.tgz",
-      "integrity": "sha512-IItsdsea19BoLC7ELy13q1iJFNmd7ofZH5+X/pJr90/nRoPEX0DJo1dHDbgtYWOhJhcCgMDTOw84RZ72q6lB+Q==",
-      "dev": true
+      "integrity": "sha512-IItsdsea19BoLC7ELy13q1iJFNmd7ofZH5+X/pJr90/nRoPEX0DJo1dHDbgtYWOhJhcCgMDTOw84RZ72q6lB+Q=="
     },
     "graceful-readlink": {
       "version": "1.0.1",
@@ -8122,7 +8278,6 @@
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/jsonfile/-/jsonfile-4.0.0.tgz",
       "integrity": "sha1-h3Gq4HmbZAdrdmQPygWPnBDjPss=",
-      "dev": true,
       "requires": {
         "graceful-fs": "^4.1.6"
       }
@@ -9666,6 +9821,18 @@
       "requires": {
         "broccoli-funnel": "^2.0.2",
         "broccoli-merge-trees": "^3.0.1"
+      },
+      "dependencies": {
+        "broccoli-merge-trees": {
+          "version": "3.0.2",
+          "resolved": "https://registry.npmjs.org/broccoli-merge-trees/-/broccoli-merge-trees-3.0.2.tgz",
+          "integrity": "sha512-ZyPAwrOdlCddduFbsMyyFzJUrvW6b04pMvDiAQZrCwghlvgowJDY+EfoXn+eR1RRA5nmGHJ+B68T63VnpRiT1A==",
+          "dev": true,
+          "requires": {
+            "broccoli-plugin": "^1.3.0",
+            "merge-trees": "^2.0.0"
+          }
+        }
       }
     },
     "range-parser": {
@@ -11417,8 +11584,7 @@
     "universalify": {
       "version": "0.1.2",
       "resolved": "https://registry.npmjs.org/universalify/-/universalify-0.1.2.tgz",
-      "integrity": "sha512-rBJeI5CXAlmy1pV+617WB9J63U6XcazHHF2f2dbJix4XzpUF0RS3Zbj0FGIOCAva5P/d/GBOYaACQ1w+0azUkg==",
-      "dev": true
+      "integrity": "sha512-rBJeI5CXAlmy1pV+617WB9J63U6XcazHHF2f2dbJix4XzpUF0RS3Zbj0FGIOCAva5P/d/GBOYaACQ1w+0azUkg=="
     },
     "unpipe": {
       "version": "1.0.0",
diff --git a/package.json b/package.json
index f0ea95e..984e8c1 100644
--- a/package.json
+++ b/package.json
@@ -26,7 +26,7 @@
   "dependencies": {
     "broccoli-caching-writer": "^3.0.3",
     "broccoli-funnel": "^2.0.1",
-    "broccoli-merge-trees": "^3.0.0",
+    "broccoli-merge-trees": "^4.1.0",
     "ember-cli-babel": "^7.11.1",
     "ember-cli-htmlbars": "^4.0.0",
     "rsvp": "^4.7.0",