NSD 2.3.7 Release

This is a bug-fix release on our older maintenance branch of NSD. It includes a fixup of type WKS printing from nsd-xfer, a fixup in a call to getservbyport. There are changes in the getaddrinfo error message and a change to make it fall back to IPv4 if it fails for IPv6. A typecast is added to satisfy the compiler. Furthermore a cleanup of the text for NOTAUTH error code.