bug #54 Re-adding window.jQuery to autoProvidejQuery (weaverryan)

This PR was merged into the master branch.

Discussion
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Re-adding window.jQuery to autoProvidejQuery

By adding `window.jQuery` to `autoProvidejQuery()`, it caused problems by making `window.jQuery = require('jquery')` not work (#32). But, *not* having it causes other obvious problems (see #52).

This re-adds `window.jQuery` back. As a fix, we would document exposing jQuery as a global variable by doing this:

```js
global.$ = global.jQuery = require('jquery');
```

ping @alOneh

Commits
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9653f1e re-adding window.jQuery to autoProvidejQuery

Author: weaverryan

lib/WebpackConfig.js

@@ -244,6 +244,7 @@ class WebpackConfig {
         this.autoProvideVariables({
             $: 'jquery',
             jQuery: 'jquery',
+            'window.jQuery': 'jquery',
         });
     }