OO-1068: remove dataTables of the question pool, implement dnd on the classic flexi table, remove uilayout too

OO-1068 improve login screen, fix sites ordering and default settings, streamines sites security callback checks, added more security callbacks

OO-986: speed-up landing/resume by prevent opening a default site, don't load a default segment view in author/my course site before the activation of the site

OO-1068: allow to open several CPs and wiki at the same time in a course and navigate through their sub trees

OO-1068 compile bootstrap js, auto switch js source and js-min version based on debug flag, add config defaults for sites and personal menu