Remove NIH pane max., in favour of native support

As of tmux 1.8:
    <prefix> z to min/max a pane

http://blog.sanctum.geek.nz/zooming-tmux-panes/
Remove scrollbar from macvim
Add vim-vagrant
Set tmux's default shell to be zsh
Add rvm to $PATH. Ewwwwwwwww.