[mms] Fix possible issue creating folder tree if multiple special mailboxes appeared in the same branch (Bug #12050).
Merge branch 'master' into imp_6_1

Conflicts:
	imp/docs/CHANGES
	imp/package.xml
This got lost somewhere
Clearer
Setup drag/drop attachments just once per page
More efficient mouseover handler
More optimizations to event handlers
float is reserved - use cssFloat instead
Fix undefined variable
js cleanups