Squashed '.vim/bundle/vimple/' changes from aa116a5..5920c9e

5920c9e Use hlexists() to detect vimple highlight groups

git-subtree-dir: .vim/bundle/vimple
git-subtree-split: 5920c9e61762e32ba2969a56418795d2a128f092
Merge commit '5189a42350937bd187001d4d24ca4e747109d148'