Fixes #21. Handle invalid SoundCloud urls
Add tests for embed_video.fields
Fixes #22. Include html templates.
python setup.py test
Fix VimeoBackendTestCase.test_get_thumbnail_url
Catch VideoDoesntExistException in admin widget
Complete change log + prepare for 0.10
Release 0.9
Running on 0.10.dev
Fix docs: versionadded
Updated video template tag to accept kwargs

Some video backends support optional arguments embedded in the URL query
string that adjust how the video is displayed (e.g. Youtube supports
rel=0 which means don't show related videos).  Updated the template tag
to accept optional KEY=VALUE pairs that will be added onto the embedded
URL as a query string.  Also added support for specifying default query
strings on a per-backend basis (e.g. so that all YouTube urls have
?rel=0 added to the end).

Added appropriate tests and documentation.