Updating device configurations

[eliwinkelman]

Is your feature request related to a problem? Please describe.
The Loom configuration and other device configuration variables (e.g. eGreenhouse rail settings) can currently only be changed if you have direct physical access to a device.

Describe the solution you'd like
Allow users to specify and modify configuration settings in the Spool UI. Store these in the db.

Add 2 device API endpoints to Spool:

1. An endpoint that returns the most recent configuration settings.
2. An endpoint that returns a bool of whether the device has the most up-to-date configuration settings.

In Loom if this setting is enabled to be used:
Check the second new endpoint periodically to see if there is an updated configuration. If there is a new one, request it from the first new endpoint. If the configuration includes the Loom configuration, restart Loom using the updated configuration.

Ideally, this would also integrate with sleepynet so that an entire network of devices could receive updates.

** Additional Context **
This functionality would be particularly useful to eGreenhouse to update rail settings remotely.