Move toggle_tab_py_mode() method from class editor to class tabengine
Move toggle_tab_py_mode() method from class editor to class tabengine

It seems to me it fits better there, because it is nice if it also
calls the _refresh_properties() and _update_ui() methods of the class
tabengine.

kaio/ibus-table,mike-fabian/ibus-table,kaio/ibus-table,mike-fabian/ibus-table