Use a cross-frame compatible instanceof check - Closes #2172.

Also see
http://perfectionkills.com/instanceof-considered-harmful-or-how-to-write
-a-robust-isarray/
Ignore events not triggered by the widget listeners. Fixes #2177.
Removed unecessary argument. Closes #2178.
Accept empty responses (no JSON) for DELETE requests.
Add processing class when initializing file list. Closes #2189.
Added crop option to image versions. Closes #2187.
Test existance of image functions and log an error if they do not exist.
Show error message if creation of scaled image version fails
Updated domain check for the demo settings.

blueimp.github.com => blueimp.github.io
Merge pull request #2193 from lmartelli/master

Gracefully handle scaled version failure
Updated version number.
Prevent returning errors when uploading non-image files.
Moved _adjustMaxNumberOfFiles call into the done calllback.
Merge branch 'master' of git://github.com/blueimp/jQuery-File-Upload