Gio:
* Throw Gio::Error again, instead of just the base Glib::Error.
This was broken in glibmm 2.27.94.
(Murray Cumming)
Glib:
* build_filename(): Add method overloads to take up to 9 arguments,
for convenience.
(Fabricio Godoy) Bug #599578
* Documentation: Mark some new API as new in 2.28.
(Murray Cumming)
