Integrate with Unifi Controller

[vpetersson]

It would be desirable to collect WiFi metrics (see #10). However, it would also be great to collect WiFi data from something like a Unifi Controller using their rest api.

In order to do this, we need:

• Add a new setting in admin for adding this configuration
• Refactor sensor data to support multiple types (WiFi and BLE) along with capture type (sniff vs others)