add community representatives to front page

[SethTisue]

I don't know how to preview the site locally (that's #38), so
perhaps my HTML is mangled -- someone should check that before
merging

partially addresses #56

/cc @bvenners @tpolecat

[julienrf]

@SethTisue I use the following docker-compose.yml file and then I can render the site locally with docker-compose up, in case that helps:

version: '2'

services:
  jekyll:
    image: bretfisher/jekyll-serve
    volumes:
      - .:/site
    ports:
      - '4000:4000'

I’ll include it into the repository in case that’s useful.

[julienrf]

[SethTisue]

Thanks Julien! I added your suggested changes.