Extract rspec vim bindings to thoughtbot/vim-rspec
Move `.vimrc.local` to the bottom of .vimrc

Having this file be sourced last allows user to
overwrite the configs in `.vimrc` without having to modify it.

* fixed file's path to work with `filereadable`
Increase tmux scrollback lines
Add a config line required by vundle
Use `color.ui = auto` setting to color git output