API cleanup for Gtk# 3.0

I'm not shure if it's the intention to break api on going to Gtk# 3.0, but there is certainly a lot of room for improvement. Here are three examples I ran into the last couple of days.

* AccelGroup.ConnectByPath(string accel_path, IntPtr closure) and other connect/disconnect methods. I'm not shure how to generate a closure pointer in C#. The method probably should accept a delegate.

* Widget.Path has the signature void Path (out uint path_length, out string path, out string path_reversed). At least the length parameter can go and may be even the reversed path so the normal path string can be the return value, as to avoid ugly out parameters.

* Gtk.Accel: there are just 2 non-obsolete methods in this class. Can they also be moved to AccelMap? In general it would be nice to remove some really obsolete stuff from Gtk#.

If there is consensus on the list that these (and there are probably more too) things should be fixed, then I shall file bugzilla entries for them and try to produce some patches.

Maarten Bosmans