[zsh] Move env.zsh functions into zsh functions
[git] Move scm to git

o Move old hgrc to dotfiles-extra repo
[zsh] Move system/env.zsh to zsh/env.zsh (cleanup)
[cleanup] Move music and mutt to dotfiles-extras repo
[cleanup] Move binaries to new extras repo
[setup] Move dev setup scripts to dotfiles-extra repo
[zsh] zsh cleanup

o Move single tmux alias into zsh/aliases.zsh
[x11] Add per host xinit config
[ssh] Add projects header to project hosts