added git command and branch name tab completion, from http://code-worrier.com/blog/autocomplete-git/
Merge branch 'master' of https://github.com/dakl/dotfiles

* 'master' of https://github.com/dakl/dotfiles:
  added PYTHONPATH and updated PATH
  Delete .vimrc
  Delete .screenrc
  Delete .hushlogin
  Delete .gvimrc
  Update .functions
  Delete .curlrc
  Update .brew
  no typo correction when cd'ing
  Update .aliases