More PyGtkDepreciationWarnings avoided
There are tons of depreciation warnings like:
PyGTKDeprecationWarning: Using positional arguments with the GObject constructor has been deprecated. Please specify keyword(s) for "label" or use a class specific constructor. See: https://wiki.gnome.org/PyGObject/InitializerDeprecations
The attached patch should remove plenty of them (I don't see any ATM on my stderr).