Remove development branch warning

lib/cluster.js

@@ -108,10 +108,6 @@ function start(service) {
       cluster.workers[pid].kill();
   });
 
-  logger.warn({
-    message: "This is a development branch of GenieACS. DO NOT use in production."
-  });
-
   cluster.setupMaster({
     exec: "lib/server",
     args: [service]