Blender Git Loki

changed WM_OT_context_* operators to pass through if one of the members in the path is None, rather then raising an error.
This means if you refer to a member of an object it will fail silently if there is no active object, but if you use an invalid attribute of the object it raises an error.
The method to check this is not nice but works well enough.

also removed pageup/down keys for changing the active shape since listviews can do this now.