Suggest replacements of SHA-1 intermediate certs with known SHA-2 certs

So as more information becomes available from issue#24 we can add more certs to the `fingerprints.json` file.

Essentially think this works but @konklone should probably go over the code. Also I've added a simple check to only run the `.sha2URL` method when we aren't looking at a root certificate. Could probably make that check step even better as we wouldn't need to run the method on the site's actual certificate.
I tried pasting [this URL](https://knowledge.verisign.com/support/ssl-certificates-support/index?page=content&amp;actp=CROSSLINK&amp;id=AR2064) into a browser tab and it took me to a 404 page.