Allow specifying -a : to disable auth

configs/standalone.js

@@ -33,7 +33,6 @@ module.exports = function(config, optimist) {
             .describe("hosted", "Use default config of the hosted version")
             .default("hosted", false)
             .describe("auth", "Basic Auth username:password")
-            .default("auth", ":")
             .describe("collab", "Whether to enable collab.")
             .default("collab", config.collab)
             .describe("cache", "use cached version of cdn files")
@@ -91,11 +90,11 @@ module.exports = function(config, optimist) {
         require("child_process").exec("tmux -L cloud91.9 kill-server", function(){});
 
     var isLocalhost = host == "localhost" || host == "127.0.0.1";
-    if (argv.auth == ":" && !isLocalhost) {
+    if (argv.auth !== ":" && !isLocalhost) {
         console.log("Authentication is required when not running on localhost. Please use -a user:pass.");
         process.exit(255);
     }
-    var auth = argv.auth.split(":");
+    var auth = (argv.auth || ":").split(":");
 
     var plugins = [
         {