Added support for mustang
Merge branch 'master' of github.com:pwolfram/dotfiles

* 'master' of github.com:pwolfram/dotfiles: (47 commits)
  updated update script
  removed unneeded alias
  changes for proxy out
  Changes fixing proxy issue/core excludes issue with git
  updated path for user-installed packages
  Changes incorporating better linking, additional options.
  Changed source for vim-latex because it needed to be patched
  xml support + screen file (missing last time)
  tmux changes
  Changes to make vim more usable for general code editing.
  Changes configuring vim for fortran
  added list of installed programs via brew
  Fixed issue with less color
  Added support for tab key mappings in vimrc
  spell bug
  updated spelling list
  Changes to write spelling file
  Changes to spellfile
  Added backup for spell checker for vim
  Fixed rainbow parentheses
  ...