Formalise the deployment for the code

[jmgasper]

Right now, the proof of concept works, but it's obviously not ideal from a deployment and documentation standpoint. We need to ensure that:

1. The processor can be deployed to Heroku via git push
2. Configuration is done through the environmental variables
3. A proper README.md exists that also covers the configuration values, including any new ones added as part of the challenge.