Issue 52:	can_undo and can_redo return None instead of boolean http://code.google.com/p/pywebkitgtk/issues/detail?id=52
Issue 52:	can_undo and can_redo return None instead of boolean
http://code.google.com/p/pywebkitgtk/issues/detail?id=52

Patch by: ccarney

jmalonzo/pywebkitgtk,jmalonzo/pywebkitgtk,jmalonzo/pywebkitgtk