Fast ctrlp

Use git ls-files on git repos and silver searcher (ag) by default by adding this to your ~/.vimrc

let g:ctrlp_user_command = {
      \ 'types': {
          \ 1: ['.git', 'git --git-dir=%s/.git ls-files -oc --exclude-standard'],
        \ },
      \ 'fallback': 'ag %s -l --nocolor --hidden -g ""'
      \ }