Merge branch 'develop' of github.com:divio/django-cms into develop
Fixes missing plugin_language, e.g. when adding 
plugins in the text plugin.
fixes #2004
Merge branch 'develop' of github.com:divio/django-cms into develop
stack docs
Merge pull request #2007 from digi604/stack-docs

stack docs
Fixes #1967
fixxes issue #1997
fixes positioning issues with django admin
fixes issue #1982
fixes an issue with the content/structure visibility when there is no placeholder. Fixes also an issue with the new positioned publish button.
Merge pull request #2009 from FinalAngel/develop

Various frontend related fixes
fixes #1932. removed twitter plugin.
new twitter pluginr reference
added other twitter plugin
Merge pull request #2011 from digi604/notwitter

removed twitter plugin.
minor publishing docs
Add apphook icon to pagetree
Merge pull request #2012 from digi604/publisher_docs

minor publishing docs
Fixes #1841
Trivial fix for the egg_name of text plugin in requirements file
Merge pull request #2013 from yakky/feature/apphook_icon2

Add apphook icon to pagetree