Cleanup and make OSX an assumption
Squashed 'thirdparty/Vundle.vim/' content from commit 0b28e33

git-subtree-dir: thirdparty/Vundle.vim
git-subtree-split: 0b28e334e65b6628b0a61c412fcb45204a2f2bab
Merge commit '4e8df95c25dc74eb53eba5b4a9177f46610c3376' as 'thirdparty/Vundle.vim'