Fixed 404 when get throbber.gif
Named urls patterns for reference in templates overrides
Fixed 404 images/throbber.gif path was incorrect.
Relative imports fixes to be compatible with Python 3
Merge remote-tracking branch 'quein/master' into develop

Conflicts:
	rest_framework_swagger/static/rest_framework_swagger/swagger-ui.min.js
Merge remote-tracking branch 'whit/master' into develop

Conflicts:
	rest_framework_swagger/urls.py