automatically open firewall port for new tang servers

plays/tang-server.yml

@@ -10,6 +10,8 @@
   vars:
     nbde_server_port: 7500
     nbde_server_manage_selinux: true
+    nbde_server_manage_firewall: true
+    #nbde_server_firewall_zone: home
 
   roles:
     - linux-system-roles.nbde_server