Allow override of external proxy port from environment (docker-compose.yml)

hotspot_proxy_v2.py

@@ -223,6 +223,8 @@ if __name__ == '__main__':
         Debug = bool(os.environ['FDPROXY_DEBUG'])
     if 'FDPROXY_CLIENTINFO' in os.environ:
         ClientInfo = bool(os.environ['FDPROXY_CLIENTINFO'])
+    if 'FDPROXY_LISTENPORT' in os.environ:
+        ListenPort = os.environ['FDPROXY_LISTENPORT']
         
     
     CONNTRACK = {}