Add option to push to Heroku

[damienlethiec]

I would be awesome to be able to deploy directly our app to Heroku at the end of the template. We should directly include the right config and add-ons (Redis for example).

• Generate a Heroku Pipeline (https://devcenter.heroku.com/articles/pipelines)?
• Automatically back-up database
• Add an error manager add-on (I am used to Rollbar but open to try new ones)
• Add a log manager add-on (any suggestions?)