Heroku Database upgrade / update steps

1. Create a follower
2. Let follower catchup
3. Check if follower is caught-up heroku pg:info -a powr-staging
4. Upgrade follower database heroku pg:upgrade FOLLOWER_DATABASE_NAME -a powr-staging
5. Note, when you upgrade, it will stop unfollowing and database becomes writable.
6. Detach and re-attach new database
7. heroku addons:detach DATABASE -a powr-staging
8. heroku config:add DATABASE_URL=URL -a powr-staging

TODO: maintenence mode pg:wait for couple of mins (status update) wait couple of days before destroying old one