Prettify Tmux status

The majority of these changes are taken from @rking's tmux.conf.  Below is an example of what it looks like.  You'll want to take note of the nice little UTF-8 arrow that alerts you to what window you are one, and the borders that update when switching between panes.

*The theme of my terminal is Solarized light (which doesn't affect these tmux settings), unfortunately the process of turning it into a GIF altered the colors a bit.*

Hope you all like it!     :neckbeard: :bowtie:  :neckbeard:  :bowtie:  :neckbeard:
![example_output](http://i.imgur.com/NJZ0OTa.gif)