OO-2676: simplify html code of calendar event editor and repository info editor, replace synchronized in velocity with a ConcurentHashSet to reduce lock contention, remove double update method for groups...

OO-2603: selenium test to test suspended test in a course, remove fieldset in fieldset in calendar form

OO-2585: filter certain properties for Google Calendar only (class:private, openolat x properties...)

OO-2541, OO-2536: optimize resolve method of merge source for the standard case, add virtual "finished" folder for finished courses, lazy load quota for the course container

OO-2409: properly set a right margin for the help and subscription to let enough place for the open button

OO-2019: fix date formatter for recurring id, set the recurrence until date at the end of the day like iCal