add route for up/down voting comments

protocol is as follows, with direction either "up" or "down", and id
being the comment id:

curl -d '{"direction": ["up"], "id":["527ffabf153f730000000009"]}' -H 'content-type:application/json' http://localhost:1337/vote
Merge branch 'master' of github.com:pbirsinger/launchbaby