Added extra env var for configuring the mediaserver external IP

This is necessary so that the SIP client knows where to connect. When not set, the startup scripts assume the mediaserver is listening on the docker internal ip address, which is not always accessible - e.g. from the macOS host, since docker is running in a VM.

Author: gsaslis

docker-compose.yml

@@ -26,6 +26,7 @@ services:
     environment:
       ## =============================== IMPORTANT!!    While most of the below defaults should be fine, YOU PROBABLY NEED TO CHANGE THIS!!
       RCBCONF_STATIC_ADDRESS: 127.0.0.1   # YOUR LOCAL IP ADDRESS GOES HERE.
+      RMSCONF_EXTERNAL_ADDRESS: 127.0.0.1  # YOUR LOCAL IP ADDRESS GOES HERE.
       ## =============================== IMPORTANT ========================================================================================
 
       # ENVCONFURL: https://raw.githubusercontent.com/RestComm/Restcomm-Docker/master/env_files/restcomm_env_locally.sh