core: Make grl_init_get_option_group() available to bindings
core: Make grl_init_get_option_group() available to bindings

Now that it's registered as a boxed type.

See https://bugzilla.gnome.org/show_bug.cgi?id=743349

https://bugzilla.gnome.org/show_bug.cgi?id=743351

jasuarez/grilo,grilofw/grilo,jasuarez/grilo,grilofw/grilo,MathieuDuponchelle/grilo,GNOME/grilo,jasuarez/grilo,MathieuDuponchelle/grilo,GNOME/grilo,grilofw/grilo,MathieuDuponchelle/grilo