Dual GLib imports

[diamondburned]

Right now, some packages are importing 2 (two) different GLib packages:

• github.com/diamondburned/gotk4/pkg/glib (ours)
• github.com/gotk3/gotk3/glib (theirs)

The obvious issue here is that their GLib contains certain types, such as Object, that we rely on. However, our GLib package also has certain parts that other packages rely on. This causes colliding imports.

The legitimate solution here is to allow import aliases to be added, which means each *girgen.ResolvedType must be aware of the new package name that is used in the qualifier. In other words, it can no longer that the base name is always the right package name. This unfortunately requires a bit refactoring in a lot of places.

An alternative solution would be to maintain a copy of their GLib package and to copy-paste everything on generation. This has the awful disadvantage of being way too ugly as well as needing to make sure the copy is regularly up to date for a very long time.

[diamondburned]

Branch https://github.com/diamondburned/gotk4/tree/dual-glib is made to attempt to fix this issue by adding import aliases. The issue will be kept open just in case until everything has been resolved.

[diamondburned]

Fixed in 470cbd9.