dotfiles: modify vimrc to use new Vundle
dotfiles: modify vimrc to use new Vundle

vundle's new version is Vundle.vim, use it.

Change-Id: I26766b688fa5cf95ba0dffc8b97956a11d55602c

smihir/dotfiles,smihir/dotfiles,smihir/dotfiles,smihir/dotfiles