Add an extra flag, WITH_INETADDRESS_HACK. Enabling this flag for build will
cause InetAddress and InetAddressType OIDs to be handled specially during
presentation. Normally they are simply displayed as hex due to being
octet-strings, but this is not how they are intended to be presented.
This allows IPv6 addresses to be presented correctly, as well as IPv4 in
emerging and existing MIBs which use the new InetAddress type.
Reviewed by: kuriyama, fenner
Tested with: snmpwalk, mbrowse