Fix default port

Author: SamyPesse

lib/configs/env.js

@@ -43,8 +43,8 @@ var parseEnv = function (env, parent, prefix) {
 module.exports = function(options) {
     var env = _.clone(process.env);
     _.each(alias, function(to, from) {
-        env[to] = env[from] || env[to];
-    })
+        if (env[from]) env[to] = env[from] || env[to];
+    });
 
     return parseEnv(env, options, 'CODEBOX');
 };