neovim: use cpsm for ctrlp matching
neovim: use cpsm for ctrlp matching

There are some cases where I prefer ctrlp-py-matchers behaviour, but
cpsm is really far superior in finding similar files, matching ctags
(ctrlp-py-matcher was practically useless), and general source files. It
seems to be slower though when executed from my home dir (some limit in
ctrlp-py-matcher?) and is maybe a bit too reluctant to match my vimrc
when working in a different repo.

paretje/dotfiles,paretje/dotfiles,paretje/dotfiles,paretje/dotfiles,paretje/dotfiles