Reindent Glade files using Glade

During the migration to GtkBuilder, most of the Glade files were edited
by hand instead of using Glade, since it was much more convenient for
the mass-changes that had to be done.
However, Glade doesn't really agree with the XML ordering, and used to
reorder everything, just upon saving an unmodified file (and removed
some "useless" properties).
I saved them again with Glade this time, fixed some properties which
disapeared; now, files content should be more stable when edited with
Glade.