Add bundle/puppet-ext-vim (manually extracted the subtree the pupet repo)

Copied ext/vim/* and LICENSE from the puppet repo to
bundle/puppet-ext-vim.

Commands used:

    git fetch https://github.com/puppetlabs/puppet master
    destdir=bundle/puppet-ext-vim
    commit=$( git rev-parse FETCH_HEAD )   # 90aad3fff7d270ef2683f486cdf999c003510cf0
    tree=$( git ls-tree --full-tree $commit ext/vim | cut -f1 | cut -d' ' -f3 )
    tree2=$( git ls-tree --full-tree $commit LICENSE | git mktree )
    git read-tree --prefix=$destdir $tree
    git read-tree --prefix=$destdir $tree2
    git commit