Added manage_subobject/no_manage_subobjects options to gfx create/modify egroup.  https://tracker.physiomeproject.org/show_bug.cgi?id=2512
Added manage_subobject/no_manage_subobjects options to gfx create/modify egroup.  https://tracker.physiomeproject.org/show_bug.cgi?id=2512

cmiss/cmgui,cmiss/cmgui