and other non-portable functions on all systems.

compile with IPv6.

ten years of API evolution :-)

but the core routines are there and seem to be working.

   o  lib/ipv6.[ch] written
   o  Lexical analyser recognizes IPv6 addresses and when in IPv6
      mode, treats pure IPv4 addresses as router IDs.
   o  Router ID must be configured manually on IPv6 systems.
   o  Added SCOPE_ORGANIZATION for org-scoped IPv6 multicasts.
   o  Fixed few places where ipa_(hton|ntoh) was called as a function
      returning converted address.

by the `mergedirs' script. Few more IP address manipulation functions
and some fixes.

Complete resource manages and IP address handling.