Remove unused static code
Correct language in plugin doc
Remove VKontakteBackend backend (fixes GH-939)
Update django-social-auth and remove unused backends

Additionally adds placeholder bitbucket settings
Remove django_social_auth_trello
Fix (syntax) errors in Java client config template
Merge pull request #941 from pascalw/patch-1

Fix (syntax) errors in Java client config template
Add an option to disable notifications on newly created projects (fixes GH-945)
Strip message and exception values
Improved filtering on empty-like values for exceptions
More various coercion fixes
More minor fixes for stripping
Improved chained exception rendering
Add notation to root cause
:(
Correct root detection
Simplify culprit check
Default the culprit to the url if nothing is available
Fix truncatechars call
Remove magical settings and migrate internals to constants