Exposes loaded modules as globals.require.modules for testing convenience

This allows me to run all of the tests under the test/ directory by filename convention, rather than having to list them all.  Here's how that looks in my codebase 

tests/initialize.coffee:

    tests = []

    for module of window.require.modules
      tests.push module if module.substring(module.length - 5) is "_test"

    for test in tests
      require test
    
tests/assets/test/index.html:

    ...
    <script src="javascripts/test.js"></script>
    <script>
      $(function() {
          require('test/initialize');
          if (window.mochaPhantomJS) { mochaPhantomJS.run(); }
          else { mocha.run().globals(['selector', 'FB', 'fbAsyncInit']); }
      });
    </script>
    ...