- depricated area "headbutofs" and "headbutlen", which is now fully
replaced with view2d handling.
- needed to add header default V2D_ALIGN_NO_NEG_Y, V2D_LOCKOFS_Y seems
to not do anything atm :)
- new: running blender in debug (blender -d) will print the current
handler and operator in use (not mousemove)