Roxbot

* add `Node` base class and `examples/node.py`
* update docs (rename Bridges to Adapters)

* gps_mock, posting simulated gps data to mqtt topic
* rename `MqttAdapter.send()` to `.publish()`

* add `nodes.gps_node` (receives mqqt gps messages and aggregates them)
* add gps dataclasses in `interfaces`

* add `examples/node.py` - classless node implementation
* add `adapters.mqtt_logger.MqttLogger` that forwards python logging to a mqtt topic
* rename `bridges` to `adapters`. Also rename `MqttBridge` to `MqttAdapter`. This is to avoid confusion with
stand-alone [mqtt-bridge](https://gitlab.com/roxautomation/components/mqtt-bridge)

* move vectors to `rox-vectors` package.

* initial release after move to github and refactoring.