add env/arg sa & adm passwd + correcting docker restart behavior

README.md

@@ -3,6 +3,8 @@ Trackmania Nation Forever Docker Server
 
 You can find it on Docker Hub [lduriez/tmserver](https://hub.docker.com/r/lduriez/tmserver)
 
+Only lan dedicated is enable (internet dedicated will be added in future version)
+
 ## Exposed ports :
 * 2350/tcp game server port
 * 2350/udp game server port
@@ -10,5 +12,7 @@ You can find it on Docker Hub [lduriez/tmserver](https://hub.docker.com/r/ldurie
 * 5000/tcp xmlrpc remote control port
 
 ## Environment variables :
-* SERVER_NAME name of your server
-* SERVER_DESC description of your server
+* SERVER_NAME name of your server (default is 'Trackmania Server')
+* SERVER_DESC description of your server (default is 'This is a Trackmania Server')
+* SERVER_SA_PASSWORD superadmin management password  (default is 'SuperAdmin')
+* SERVER_ADM_PASSWORD admin management password (default is 'Admin')