OBMFULL-5656 Adds a copy constructor to Obm.DateTime.
OBMFULL-5656 Adds Obm.DateTime.addHours().
OBMFULL-5656 Renames Obm.DateTime.d to Obm.DateTime.eventStartDate.
OBMFULL-5656 Computes the length of fullday events in the free/busy view correctly.
OBMFULL-5656 Computes the offset of a full-day event correctly in the free/busy view.
OBMFULL-5656 Better free/busy handling for allday events.
OBMFULL-5190 Correct owner after restoring agenda.

Previously, the owner of a restored event was the user whose agenda was
restored.
OBMFULL-5190 Correctly set organizer in ICS->OBM conversion.