Add at least minimal CI testing #61
Description
As people start using this repo more, we need minimal CI testing.
As a bare minimum, CI testing should prove that we can deploy a server without errors.
There may have to be a hack to deal with Lets Encrypt; we won't have a public address on most CI frameworks, unless we use drone.io and test on a dedicated instance.
Perhaps we can do minimal API tests.
As a stretch goal, we'd test the migration and setup scripts.
With Node-RED 1.1 and later, the Admin API can be used to install flows; so we could potentially mock all the data injection, and then use the InfluxDB and grafana APIs to test data recording.