Add a civic.json file

[stvnrlly]

A civic.json file provides information about this project that's not included in the Github metadata. The full details of the format are here. Just put it in the root of your repo and we'll automatically display that info on the projects page.

Code for DC also has a tool to help put the file together here, and a validator to make sure everything's in the right place here.

(Also, since Code for DC is tracking this project, any issues tagged with help wanted will show up on http://codefordc.org/projects/helpwanted.html. If you are stuck on something, try that!)