- Added markers (partially) back, ed_markers.c (temporary in spacetime, where to put general stuff like this?), and added ED_markers.h for api. - Mkey in timewindow shows marker (no icon, doesnt work yet). (Adding operators gets easy :) - Noted some conflict for operator storage... with markers being used all over, added it to the screen level. - More todos: view2d is stored in space, for time, etc. With regions we could move this over, but better todo as post 2.5 project. Multiple 2d views in area would be cool though.