Switch to a vim-matchit repo that exists

- tsaleh deleted his mirror
- switch to vim-scripts version
Exclude Brewfile

It is project-specific, not intended for machine configuration.
Only set nocompatible once as early as possible

* Setting nocompatible has side effects
* Setting it again (even if set) repeats side effects
* Settings like ruler will be reset if set again
Add HISTFILE to save zsh history

History file needs to be specified or otherwise the history would not be saved
over multiple terminal sessions.
[Source](http://zsh.sourceforge.net/FAQ/zshfaq03.html#321)
Don't set $EYRC

We don't use Engine Yard anymore.
Combine zlogin settings into zshrc

* easier when everything is just one file
* most (if not all) interactive shells are login shells and we likely want those
  settings for interactive shells
Remove leftover snippets variable
Preliminary changes to thoughtbot dotfiles

* Add vim plugins for tmux, ag, i18n
* Add tmux shortcuts for splitting, resizing, and moving between windows
* Improve tmux copy/paste
Some modifications to dotfiles

* Plugin to autoclose parens, brackets, quotes, etc.
* Set cdpath for easy directory switching
* Set cursor line and 80 character lines in vim
* Misc git and zsh aliases