Import an LDNS-based implementation of host(1).
LDNS needs OpenSSL.  This wasn't a problem as long as it was only build
statically, since any program using it would have to link with it anyway.

Approved by:	re (blanket)
Import Magerya Vitaly's ldns-host, and build it instead of the BIND version
in the WITH_LDNS_UTILS case.

Approved by:	re (blanket)