Update package.json. (#24582)

1. Use the same jQuery version in jspm
2. Update the files to only include the source and dist folders

docs/4.0/migration.md

@@ -12,6 +12,7 @@ While Beta 2 saw the bulk of our breaking changes during the beta phase, but we
 
 - Removed the unused `$thumbnail-transition` variable. We weren't transitioning anything, so it was just extra code.
 - Changed the CSS for managing multiple `background-image`s on custom form checkboxes and radios. Previously, the `.custom-control-indicator` element had the background color, gradient, and SVG icon. Customizing the background gradient meant replacing all of those every time you needed to change just one. Now, we have `.custom-control-indicator` for the fill and gradient and `.custom-control-indicator::before` handles the icon.
+- The npm package no longer includes any files other than our source and dist files; if you relied on them and were running our scripts via the `node_modules` folder, you should adapt your workflow.
 
 ## Beta 2 changes
 

package.json

@@ -126,15 +126,9 @@
     "node": ">=6"
   },
   "files": [
-    ".babelrc",
-    ".eslintignore",
-    "Gemfile",
-    "dist",
-    "build",
-    "js/.eslintrc.json",
-    "js/**/*.js",
-    "js/**/*.js.map",
-    "scss/**/*.scss"
+    "dist/",
+    "js/{src,dist}/",
+    "scss/"
   ],
   "browserslist": [
     "Chrome >= 45",
@@ -205,7 +199,7 @@
     },
     "dependencies": {},
     "peerDependencies": {
-      "jquery": "^3.0.0",
+      "jquery": "1.9.1 - 3",
       "popper.js": "^1.12.9"
     }
   }