[Worker] Fixed some odd error handling on core boot.

Author: Jack12816

lib/app/worker.js

@@ -442,14 +442,14 @@ Worker.prototype.configure = function(app, server, callback)
 
         console.log(
             'Error occured while loading the '.red +
-            this.cliArgs.options.context.red.bold +
+            self.cliArgs.options.context.red.bold +
             ' context.'.red + '\n'
         );
 
-        if (e.stack) {
-            console.log(e.stack);
+        if (err.stack) {
+            console.log(err.stack);
         } else {
-            console.log(e);
+            console.log(err);
         }
 
         process.exit(1);