When checking for data to be received use the 'transport_recv_ptr'

This affects cases where there is different send and recv pointers.
Reported and investigated by JMRecio.
doc update
only fail DANE verification if status is non-zero
Accept a certificate using DANE if there is at least one entry that matches the certificate.

This corrects the previous behavior that was rejecting the certificate if there
were multiple entries and one couldn't be validated.
Patch by simon@arlott.org.

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>
increased MAX_DATA_ENTRIES to 100.
doc update