.vimrc: NeoBundle 'tpope/vim-fugitive'
.vimrc: Trivial changes
.vimrc: Use git-diff-normal for vimdiff

https://github.com/fumiyas/home-commands/blob/master/git-diff-normal
http://qiita.com/takaakikasai/items/3d4f8a4867364a46dfa3