Fix bug in graded thread view tab in course session - ref #6589
Fixing PHP warning.
Fix [start|end] date bug in quiz advanced properties when creating a quiz - ref #6586
Fixed icon in users folder in documents - loosely refs BT#6660
Deleting extra field sessions values when deleting a session see #6664
Minor - format code, doc update
Merge branch '1.9.x' of github.com:chamilo/chamilo-lms into julio6666
Minor - Removing virtual course exception in session import.
Fixing category code when creating a course see BT#6666
Fixing bug in the search ajax filemanager see BT#6675
User must logged in, to search a document.
Minor - adding isset.
Fixed issue returning student instead of teacher in certificates in sessions - refs #6694
Added new GetLearnpathHighestLessonLocation() webservice - refs BT#6667
Fix some bugs in learning path item drag-n-drop - ref #6622
Minor - format code
Minor - format code
Merge branch '1.9.x' of github.com:chamilo/chamilo-lms into julio6666
Minor - format code
course_edit.php page has an option to add/remove teachers in all course session coaches.