Plug reference leak on main signal watch source
Plug reference leak on main signal watch source

Additionally rename pygtk_signal_watch_finalize() to
pygtk_main_watch_finalize() for consistency.  Fixes bug #579406.

nzjrs/pygtk,GNOME/pygtk,GNOME/pygtk,nzjrs/pygtk,Distrotech/pygtk,GNOME/pygtk,Distrotech/pygtk,amremam2004/pygtk,nzjrs/pygtk,amremam2004/pygtk,Distrotech/pygtk,amremam2004/pygtk