Optimize common certificate loading from file/string; instead of calling
out to openssl, use the built in Crypt/X509 libraries, which is a lot faster. We still have to call out if we want the URL, since that is in another section that we cannot get, but that does not happen very often. We also fall back to the slow path for some certs that use the Authority Info Access section for the URN/UUID, since that is not available either. But for Protogeni, we are mostly on the fast path.