Initial commit: System2MQTT implementation

config.yaml.example

@@ -0,0 +1,8 @@
+mqtt:
+  host: "mqtt.example.com"
+  port: 1883
+  username: "system2mqtt"
+  password: "your_secure_password"
+  client_id: "system2mqtt_{hostname}"
+  discovery_prefix: "homeassistant"
+  state_prefix: "system2mqtt"