remove colorized log output, add timestamps

lib/utils.js

@@ -78,7 +78,7 @@ const createAppLogger = ({ dev }) => {
   return winston.createLogger({
     transports: createTransports(dev),
     format: winston.format.combine(
-      winston.format.colorize(),
+      winston.format.timestamp(),
       winston.format.json()
     ),
   })