removed the SDB databases in contrib/sdb as they hadn't been
maintained in some time, and were no longer able to link to named
without modification. also:
- cleaned up contrib/README, which still referred to contrib
subdirectores that were removed already, and linked to an obsolete URL.
- removed references to sdb in doc/misc/roadmap and doc/misc/sdb.
4708. [cleanup] Legacy Windows builds (i.e. for XP and earlier)
are no longer supported. [RT #45186]
4707. [func] The lightweight resolver daemon and library (lwresd
and liblwres) have been removed. [RT #45186]
4706. [func] Code implementing name server query processing has
been moved from bin/named to a new library "libns".
Functions remaining in bin/named are now prefixed
with "named_" rather than "ns_". This will make it
easier to write unit tests for name server code, or
link name server functionality into new tools.
[RT #45186]