Merge pull request #9 from walterwootz/patch-1

Added IoT Agent OPCUA to the list

Author: jason-fox

docs/iot-agent.md

@@ -46,6 +46,8 @@ the following:
     UltraLight2.0 payload) and NGSI
 -   [IoTAgent-LoRaWAN](https://fiware-lorawan.readthedocs.io/en/latest) - a bridge between the
     [LoRaWAN](https://www.thethingsnetwork.org/docs/lorawan/) protocol and NGSI
+-   [IoTagent-OPCUA](https://iotagent-opcua.readthedocs.io/en/latest/) - a bridge between the
+    [OPC-UA](https://opcfoundation.org/about/opc-technologies/opc-ua/) protocol and NGSI
 
 ## Southbound Traffic (Commands)