Unhandled exception

[ryuuzake]

PR for #28

1. Add original DioError to DirectusError
2. Handle error from manuallyRefresh in refreshExpiredTokenInterceptor

[ryuuzake]

I still don't know how to test the dio interceptor handling the reject sent from refreshExpiredTokenInterceptor

Do you have any idea?

[apstanisic]

Probably by making some other request while access token is expired.
That way sdk should try to update token first, and we mock an error in manuallyRefresh. That way request should throw an error. I'll try to figure out the way soon

[apstanisic]

Thanks for the PR. I've open another issue for test #30