Extract dev/staging/prod binaries to parity gem

https://github.com/croaky/parity
Add user details.
Add easier navigation between split-windows.
Use bundle to execute rspec.
Add the Solarized colours bundle.
Change colour scheme to Solarized.
Add heroku to the path.
Add easy swapping for Rails projects.
Add an alias for bundle exec.
Install TMUX Powerline.
Add an alias for TMUX.
Hide the status bar.
Replace thoughtbot scripts with Matt's.
Always show the tab bar.
Add an 80-character limit.
Update prompt for powerline.
Load RVM at startup.
Add a cap alias.
Add a branch alias.
Remove alias for branch.