OO-1939: catch rs closing the course, streamlined the initialize of the course editor to prevent to reload and reload the course and the repository entry

OO-1924: if a single user is selected with the edit bulk action in members list, show the personalized edit dialog

OO-1919: try to find more informations for a good warning message if group/areas are renamed and / or deleted in enrollment course element

OO-1926: added formaDateRelative to formatter to add a specific period of time to a baseline date and format it short. made it available in the phantomJS certificates

OO-1914: if the SCORM resource in a course element is missing, show a message instead of a red screen.