Update dependencies and bump to 2.1.0

Update dependencies, do not mask HTTP/OpenSSL exceptions, do not fall…

…back to HTTP (#4)

if HTTPS is not available

The Webfinger spec now mandates a standard URL. Check that URL first,…

… instead of

checking host-meta first (which may actually not be present). Bump to 1.2.0

Raise exception on invalid mime type of Webfinger response

Removed unneeded runtime dependency

Implemented RFC 7033

Goldfinger::NotFoundError and Goldfinger::SSLError added

First release