Groups - confirmed working (at a basic level at least)

[Tediore]

First I'd like to say thank you for creating this external component. This is awesome, and I've already created several Zigbee devices with it. I saw the note in the readme about groups not being tested, and I wanted to share that I've tested groups with two devices that have single channel dimmable lights, and everything appears to be working properly. I have this in the same endpoint as the on/off and level control clusters:

        - id: GROUPS
          attributes:
            - attribute_id: 0
              id: attr_groups
              type: 8BITMAP
              value: 0

The only attribute is the NameSupport attribute (whether or not group names are supported) which is mandatory, and the value of 0 is for "not supported." I haven't tested it with the value set to supported.

Joining a group, leaving a group, and controlling power and brightness all work as expected.