Switch from GtkBuilder to using GtkTemplate.
Rename widget IDs to be more readable.
Drop widget IDs that are not used.
Move code into the .ui file that can be.
Connect signals in swapped form.
The current widget has a very generic name "EditDialog" - rename it to something
that reflects better what it is for.
Implement it is as a full GtkWidget using GtkTemplate.
Move some of the logic from inside the dialog to the code that creates the dialog
so less data is passed around.
Store properties using functions instead of g_object_set_data - that passes
everything as a gpointer which is easy to make a mistake with.
Recent versions of Gettext are able to translate several formats
that are used in GNOME applications. This patch migrates from
Intltool to Gettext by using meson's i18n features.
https://bugzilla.gnome.org/show_bug.cgi?id=787588
Meson is a build system focused on speed an ease of use, which
helps speeding up the software development. This patch adds meson
support along autotools.
https://bugzilla.gnome.org/show_bug.cgi?id=785414
