Add wp-checkout component tests

package.json

@@ -187,6 +187,7 @@
 		"source-map-support": "0.5.12",
 		"store": "2.0.12",
 		"striptags": "2.2.1",
+		"styled-components": "4.4.0",
 		"superagent": "3.8.3",
 		"svg4everybody": "2.1.9",
 		"textarea-caret": "3.1.0",
@@ -201,6 +202,7 @@
 		"valid-url": "1.0.9",
 		"webpack-bundle-analyzer": "3.5.0",
 		"webpack-dev-middleware": "3.7.0",
+		"wp-checkout": "file:packages/wp-checkout",
 		"wpcom": "5.4.2",
 		"wpcom-proxy-request": "5.0.2",
 		"wpcom-xhr-request": "1.1.3",

packages/wp-checkout/.babelrc

@@ -0,0 +1,3 @@
+{
+  "presets": ["@babel/env", "@babel/preset-react"]
+}