OPENDJ-2855 Check Subject Alt Names in the CheckHostName TrustManager
The behaviour in RFC 4513 surrounding the criticality flag for the SAN extension is not clear.
This change checks the SAN first, and will hard fail if the SAN is critical and either doesn't match the hostname, or contains uncheckable GeneralNames.
The fallback to the popular (but very deprecated) hack of looking for the lowest CN in the subjectDN is only performed if the SAN is non-critical and does not match.
InetAddressValidator is added from the Apache Validator project.