Return original error when the request went wrong.

Sometimes the request to the Google Maps API does not return a valid JSON response. This happens eg. if the request times out or of the credentials are wrong.

Before you got this message:

```
[SyntaxError: Unexpected token u]
```

Now you get some more the original error:

```
{ [Error: getaddrinfo ENOTFOUND] code: 'ENOTFOUND', errno: 'ENOTFOUND', syscall: 'getaddrinfo' }
```