Update README.md

add example of how to use a LightService::Action as a LightService::Organizer
Add Code Climate Badge

I made code climate track your repo. It's free for open source projects. You will have to create an account if you want it to notify you.

Btw, notice that your repo gets a perfect 4! No code smells so far. :+1
Merge branch 'patch-1' of https://github.com/padi/light-service

* 'patch-1' of https://github.com/padi/light-service:
  Add Code Climate Badge