[imp] Implementing popup warning if no items are selected when marking as read or unread. Fixes #4811

Adding space before comma

Adding space before comma

Adding space before comma (had it right the first time!)
[fix] "Save as copy" button of User Group. Fixes #4778. Fixes #4798

Add return false if group could not be saved

Change name of method to fix notice errors
Restructure JDocument tests and add additional cases
Merge branch 'staging' of github.com:joomla/joomla-cms into 3.4-dev
Merge branch '3.4-dev' of github.com:joomla/joomla-cms into 3.4-dev