Set domain and commit

src/freedombone-app-mediagoblin

     function_check add_ddns_domain
     add_ddns_domain $MEDIAGOBLIN_DOMAIN_NAME
 
+    set_completion_param "mediagoblin domain" "$MEDIAGOBLIN_DOMAIN_NAME"
+    set_completion_param "mediagoblin commit" "$MEDIAGOBLIN_COMMIT"
+
     APP_INSTALLED=1
 }