Fixes for v0.4.x

- [ ] Find a fix for commander.js bug: --option flag definition not working properly #38
- [ ] Improve the `WordPress Development Server` 
Update the message like;
```
WordPress Development Server started at Tue Feb 21 2017 22:52:50 GMT+0530 (+0530)
Listening on http://localhost:8888
Document root is /var/www/
Press Ctrl-C to quit.
```