Fixed cutting of objects in left oriented coordinate space.

Removed some spurious debugging printf.

src/slic3r/GUI/GUI_ObjectList.cpp

@@ -507,7 +507,6 @@ void ObjectList::key_event(wxKeyEvent& event)
         || event.GetKeyCode() == WXK_BACK
 #endif //__WXOSX__
         ) {
-        printf("WXK_BACK\n");
         remove();
     }
     else if (wxGetKeyState(wxKeyCode('A')) && wxGetKeyState(WXK_SHIFT))