Error during render not being logged sometimes
The current logging on failed server-side render appears to be insufficient. Currently this is what it looks like:

```
      const errorHandler = err => {
        if (err && err.code === 404) {
          res.statusCode = 404
          res.end('404 | Page Not Found')
        } else {
          // Render Error Page or Redirect
          res.statucCode = 500
          res.end('500 | Internal Server Error')
          console.error(`error during render : ${req.url}`)
          console.error(err)
        }
      }
```

It seems that since 'err' is an actual JavaScript error object (or null) that sometimes nothing is logged. I have found something like this to be much more useful:

```      
   const errorHandler = err => {
        if (err && err.code === 404) {
          res.statusCode = 404
          res.end('404 | Page Not Found')
        } else {
          console.log(`error during render : ${req.url}`);

          if (err) {
            console.log(err.stack);
          } else {
            console.trace();
          }

          // Render Error Page or Redirect
          res.statucCode = 500
          res.end('500 | Internal Server Error')
        }
      }
```