Updated User Interface for Bootstrap 2.0.
Add stop method stub to avoid lifecycle exceptions.
Move upload handler class into its own file.

Fixes #996.
Updated README.
Reorganizing the plugin files into folders.

Adding comments to every included resource in index.html.
Only make XDomainRequest Transport available if cross-domain XHR requests are not available.
Updated files list.
Fixed the path to the progressbar image.
Add bottom margin to both buttons and inputs.
Added demo upload server check.
Enable upload server status check only for browsers with CORS support.
Make sure the animated progress bar background is applied.
File input button CSS fixes for IE7+IE6.
Move the IE6+IE7 CSS fixes into the external stylesheet.
Updated package keywords list.
Added new events for the UI version (added started sent completed failed stopped destroyed).
Render existing files by calling the done callback.
Give the buttons a larger span than the progress bar.
Use a HEAD request for the upload server status check.
Use $.ajaxSettings.xhr() to retrieve the XHR object.