chore(package.json): add commonjs support

See angular/angular.js#10732

Closes #14

README.md

@@ -14,21 +14,12 @@ You can install this package either with `npm` or with `bower`.
 npm install angular-resource
 ```
 
-Add a `<script>` to your `index.html`:
-
-```html
-<script src="/node_modules/angular-resource/angular-resource.js"></script>
-```
-
 Then add `ngResource` as a dependency for your app:
 
 ```javascript
-angular.module('myApp', ['ngResource']);
+angular.module('myApp', [require('angular-resource')]);
 ```
 
-Note that this package is not in CommonJS format, so doing `require('angular-resource')` will
-return `undefined`.
-
 ### bower
 
 ```shell

index.js

@@ -0,0 +1,2 @@
+require('./angular-resource');
+module.exports = 'ngResource';

package.json

@@ -2,7 +2,7 @@
   "name": "angular-resource",
   "version": "1.3.14-build.55+sha.0cf170d",
   "description": "AngularJS module for interacting with RESTful server-side data sources",
-  "main": "angular-resource.js",
+  "main": "index.js",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1"
   },