chore(vim): set up g:completion_chain_complete_list
chore(vim): set up g:completion_chain_complete_list

Let's see if this makes our filename completion a little bit cleverer.

wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent