Removing p5-gtk, p5-Gdk-Imlib, p5-Gdk-Pixbuf

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

If noone actively asks for them to stay, I'd like to remove p5-gtk,
p5-Gdk-Imlib, and p5-Gdk-Pixbuf.

They contain perl bindings to GTK1 libraries, and are quite
unmaintained.

Nothing in pkgsrc uses them.

Please let me know if you still do use them.
 Thomas

(Reason: I just had to fix p5-gtk to build with perl-5.16, and it
probably wasn't worth my time, so I'd like to avoid it in the future.)