adds language tabs on page creation
fixes issue #2925
breadcrump working again
use tabs
only modify params on tree view. fixes #2926 and #2927
show more error infos and refresh after error
Merge pull request #2974 from digi604/fix-2946

adds language tabs on page creation
come out of force language on exception
Merge branch 'develop' of github.com:divio/django-cms into develop
Merge branch 'develop' into fix-2938
invalidate page cache on restart
updated docs
pyflakes fixes
add never cache headers for dynamic pages
cleanup
Merge pull request #2977 from digi604/fix-2938

Fix 2938 (cache invalidation on restart)
fixes issue #2949
remove console.log
Merge pull request #2978 from FinalAngel/develop

Fixes filter and param issues within sideframe
fixes #2980