Gir

This series of patch provides a first version of GIR file generation.

There's a lot of TODO in the code because there's some information that's difficult to get from the source, like the params ownership, the inheritance classes, interfaces and so, but I've left a default value from now, to be implemented in the near future.

This version is functional for small examples. I wrote an example that tests the generated gir using python: https://gitlab.gnome.org/danigm/gnome-class-example/