Script for provisioning a development environment.

Automates and updates the developer tools instructions that are
currently at
http://docs.swiftnav.com/wiki/HOW-TO:_Setting_up_developer_tools_for_Piksi. This
has only seriously been tested on OS X 10.9.* on my personal machine so far.

r=@fnoble,@cbeighley,@njoubert,@imh,@kovach,@gsmcmullin
Added splash screen citation.
Fixing bugs from feedback, misc. improvements.

Addresses several issues around boostrapping the OS X install, leaving
out Python virtualenvs. Also, includes a Vagrantfile for testing the
Linux installation.

Linux tested via Vagrant. Tested OS X with a virgin account.

r=@cbeighley,@kovach,@fnoble
String formatting and fix to homebrew installation.
Fixing pip sudo when not using virtualenv.
Merge pull request #112 from mookerji/autobot

Script for provisioning a development environment.