Add the necessary machinery to generate the introspection data from eom

Annotations are still missing, but this provides enough for basic introspection usage

Based on eog commit b316c9e0b30a8c6d67feb8f21a20268e18c8cc3d
From Claudio Saavedra <csaavedra@igalia.com>
Dont use EomExifData in the C api

Eog bug https://bugzilla.gnome.org/show_bug.cgi?id=626257
Based on eog commit f457e6cd2f9b25194145681109ae4bd7f3b4ee7f
From Claudio Saavedra <csaavedra@igalia.com>