Clarify other options and re-order a bit.

Added ldap_pvt_tls_get_strength() - return encryption strength, for
use as a SASL session security factor.

ITS#658: man page
 from Tom Jordan <tjordan@doit.wisc.edu>

input.  In input==NULL, returns FQDN of local host.
Fixed copy_hostent() uninitialized pointer bug.
Replaced gethostname calls with ldap_pvt_get_fqdn( NULL ) calls.