Blender Git Loki

- Do not use old anchor toggling operator. It used to set brush flags to
unawaliable state.
- Also changed dynamic space bar menu, so it now also wouldn't allow to
set brush stroke flags to unavaliable state.

Also tried to remove use_anchor, use_space, use_restore_mesh and
use_airbrush, so user would be unable to set flags to unavaliable state,
but it was quite difficult for non-sculpt paint modes. They don't support
all of stroke methods, so brush.stroke_method can't be used for them.

Keep this area unchanged for now.