Auto merge of #4888 - seanpdoyle:vendor-shim-blueprint, r=stefanpenner

Introduce the `vendor-shim` blueprint

There isn't much documentation around how to properly wrap an otherwise
global `window` dependency in an ES6 compliant module.

The generated blueprint will nudge consumers in the correct direction.

Insprired by [this stack overflow response][shim].

[shim]: http://stackoverflow.com/questions/30443351/import-dependencies-in-ember-cli-e-g-import-math-js/30584671#30584671

blueprints/vendor-shim/files/vendor/shims/__name__.js

@@ -0,0 +1,9 @@
+(function() {
+  function vendorModule() {
+    'use strict';
+
+    return { 'default': self['<%= name %>'] };
+  }
+
+  define('<%= name %>', [], vendorModule);
+})();

blueprints/vendor-shim/index.js

@@ -0,0 +1,17 @@
+/*jshint node:true*/
+
+var stringUtil = require('ember-cli-string-utils');
+
+module.exports = {
+  description: 'Generates an ES6 module shim for global libraries.',
+
+  locals: function(options) {
+    var entity  = options.entity;
+    var rawName = entity.name;
+    var name    = stringUtil.dasherize(rawName);
+
+    return {
+      name: name,
+    };
+  },
+};

tests/acceptance/help-test.js

@@ -752,6 +752,13 @@ ember version \u001b[36m<options...>\u001b[39m' + EOL + '\
                   anonymousOptions: ['name'],
                   overridden: false
                 },
+                {
+                  name: 'vendor-shim',
+                  description: 'Generates an ES6 module shim for global libraries.',
+                  availableOptions: [],
+                  anonymousOptions: ['name'],
+                  overridden: false
+                },
                 {
                   name: 'view',
                   description: 'Generates a view subclass.',