Renamed addPlugin.js to pluginCreator.addPlugin.js
For pluginCreator.addPlugin tests, use testPlugin as name for the testing plugin.
Tweaked CommonJS export mechanics such that if a global document or window object is not available the module instead exports a factory function accepts a configured jQuery object in order to produce a working pluginCreator.
Rewrote test/common.js to use jsdom in a more non-asynchronous fashion.
Updated test/pluginCreator.addPlugin.js to reflect changes to test/common.js
Renamed test/pluginCreator.addPlugin.js to test/jQuery.addPlugin.js to reflect content in file.
Added test/jQuery.fn.testPlugin.js