tmux: Preserve Gnome, DBus, GPG env vars

This permits tmux sessions to connect to the GPG agent and current Gnome and
DBus sessions.

Home-Tag: public
vim: Teach Piglit plugin about PEP8 and new 'piglit' script

Home-Tag: public
git-stamp: Add script

Home-Tag: public
Merge branch 'public/master'

Conflicts:
	bin/git-stamp