Automated deployment

[technicalpickles]

It'd be nice to be able to deploy hubot from hubot 😂

I think we can configure Heroku/GitHub integration to automate deploying on merge. Internally at GitHub, we use branch deployment for validating changes before doing a merge, so it'd be nice to have something similar here. I could imagine this being useful for testing hubot releases with hubot-for-hubot in particular.

I haven't used it personally, but https://github.com/atmos/hubot-deploy is what we've typically recommended to get started.