* Fix `MatchDomainName` to also check for remaining len on success check.
* Enhanced `DNS_entry` to include actual ASN.1 length and use it thoughout (was using XSTRLEN).
Added additional tests for matching on domain name:
* Check for bad common name with embedded null (CN=localhost\0h, Alt=None) - Note: Trouble creating cert with this criteria
* Check for bad alternate name with embedded null (CN=www.nomatch.com, Alt=localhost\0h)
* Check for bad common name (CN=www.nomatch.com, Alt=None)
* Check for bad alternate name (CN=www.nomatch.com, Alt=www.nomatch.com)
* Check for good wildcard common name (CN=*localhost, Alt=None)
* Check for good wildcard alternate name (CN=www.nomatch.com, Alt=*localhost)
