this adds a debug indication and versioning display. Fixes #1844 and #2033
Merge branch 'develop' of github.com:divio/django-cms into feature/fixes
added upated retina image
add delay before drag starts
use public methods instead of private, small rewrite of toggleToobar
we should display all messages, not just the latest
use "Dvelopment version" instead of "Debug" for better UX
added missing colon and removed unused param
change delegate and reset to privat emethods
Merge branch 'develop' of github.com:divio/django-cms into feature/fixes
add basic cut_plugin mechanisms
Merge pull request #2065 from FinalAngel/feature/fixes

Visual Debug Information
fixes issue #2072
add alternating colors
separate nestedSortable to its own file for debugging
decrease delay and not animate empty placeholders anymore
Fix broken tests:

since MLNGPlaceholderActions.de_copy_languages doesn't enforce order on the returned languages,
comparing lists in tests might give false positives
=> we need to assert sets are equal
this fixes an issue where the settings are not set correctly
hide expandables per default
additional css for supressing drag & drop issues