Our build files were relying 'sysroot' to find gexiv2.h but this is
not possible with Apple Clang om which sysroot points to macOS SDK.
So, exotic environments like Homebrew were failing. Let's fix this.
gtk_accel_map_load()/gtk_accel_map_save() are not working with the new
GAction-based code. GtkApplication does not seem to have helper functions to
simply load and save accelerators in a file, so we just implement it ourselves.
A few things are missing right now, namely:
- On parsing, it doesn't handle any kind of duplicate accelerators (possible
especially if someone edited the new shortcutsrc manually).
- On reading, maybe we should only write down the changed (from defaults)
actions, while keeping the old ones commented-out, as menurc used to be. This
is actually useful info both for debugging or even for users who want to look
at this file and see what they changed.
- We should add import code to transform the menurc into shortcutsrc when
updating GIMP, otherwise all custom shortcuts would get lost.
There is still the question on whether we should add the group name too. I think
we should, expecially for plug-in's procedure actions, though right now these
are just added in the GtkApplication's main action group anyway. I'll see later
to refine this.
