[boxes] introduce new boxes system * separate box content generation from its layout * refactor css classes to allow moving boxes and still get consistent ui On the way to contentnavigation/boxes unification (in a later patch) * * * some fixes for the previous (default_new_boxes_system) patch * * * some fixes for the previous (default_new_boxes_system) patch

option_group_changed('cleanup-session-time', 'web', 'main')