Vim: updated plugin submodules
Bash: set $PS1 color based off hostname

This adds a small python script, hashcolor, which takes a string and
hashes it to a xterm-256 color code for both foreground and background.
Then, in .bash_profile, we set the prompt color based off of hashing
$HOSTNAME.
Update Vim and tmux for latest powerline

Vim now starts Powerline in the newly reccomended, more pythonic way.
tmux also makes sure to run powerline-daemon when it starts, which makes
its status line look SUPER snazzy.
Vim: update plugin submodules