HomeAssistant API token (#303)

* Add a uuid to home-assistant

* Add API_TOKEN to homeassistant

* Update homeassistant.py

* Update addon.py

hassio/docker/homeassistant.py

@@ -54,6 +54,7 @@ class DockerHomeAssistant(DockerInterface):
             environment={
                 'HASSIO': self._docker.network.supervisor,
                 'TZ': self._config.timezone,
+                'HASSIO_TOKEN': self._homeassistant.uuid,
             },
             volumes={
                 str(self._config.path_extern_config):