Use uuid in devices & tidy up

- Generate UUID for device_id (previously sha-1)
- Update datasets, sensors, devices and comparison UI to work with UUIDs.
- Make device's description editable
- Remove: sha-1 namespace, csv files that were used in etl.clj and outdated etl.url.clj
- Tidy up etl in dev - uses generated data only. Works with current API.

Fixes #462