title: RequireJS - What is the purpose of the "exports" property in shim
body: <p>What is the purpose of the "exports" property in the shim below? Is it really required?</p>
  
  <pre><code>requirejs.config({
      shim: {
          'backbone': {
              deps: ['underscore', 'jquery'],
              exports: 'Backbone'
          }
      }
  });
  </code></pre>
  
  <p>I ask because it seems redundant - when the module is included in a dependency list, we will specify the exported name again as the function argument:</p>
  
  <pre><code>define(['backbone'], function (Backbone) {
    return Backbone.Model.extend({});
  });
  </code></pre>