intltool is unmaintained nowadays while upstream gettext gained
support for formats like GSettings schemas and .desktop files,
and offers a mechanism to teach it about other XML formats not
yet supported out of the box which we can use for the rest.
So there's nothing stopping us, just make the switch ...
https://bugzilla.gnome.org/show_bug.cgi?id=769074
We can autodetect what to do based on the user's session, so drop
the separate desktop files.
This, along with some future changes, will enable us to be bus
activatable.
https://bugzilla.gnome.org/show_bug.cgi?id=741666