OO-1980: better check model boundaries and deselect the table multi selection if the search arguments have changed

OO-1979: check if the selected page for the single page course element is really a file and not a directory

OO-1971: fix deselect of course element in reused course link panel, clean up callout after a link is clicked

OO-1946: fire event per type, use the official method to check if we are on the "cluster" node which send the event

OO-1945: better naming of user course environment, use the course environment of the assessed identities to update the score...

OO-1942: update the database first and reload the calendar after to prevent recursive reloading the same calendar or calendar with an error