Implementing parts of seahorse in vala

[Stef <stef-list memberwebs com>]

I'm working on splitting out the PGP, SSH and Gnome Keyring
functionality into separate modules inside of seahorse. This is tedious
work. It would be even more tedious if I had to do it in C :)

I'm doing a lot the implementation in vala. I hope this is okay with
everyone. Vala compiles down to C/GObject code, and is an awesome way of
writing GObject code.

This is not a rewrite of seahorse, it's moderately simple to bridge the
old seahorse C code and call it from vala. Vala obviously compiles down
to C and so can be called from C easily.

It's not a requirement that everyone has a vala compiler installed
either, as I'll be checking in and distributing the generated C code
along with seahorse.

Nothing is checked in yet. Before I go ahead with that, I want to see if
anyone had any problems with this plan.

Cheers,
Stef