Fix masking and printing of IPv4 and IPv6 prefixes

Make output of IPv6 addresses consistent across valuepair printing functions
Fix ntohll so that it works on big endian systems

Add ntohlll to reverse 128 bit unsigned integers

Add function to print 128 bit unsigned integers

Add configure checks for 128 bit integers
Print IPv6 address IPv6/prefix IPv4/prefix as integers in %{integer:}
Fix CIDR comparison (master branch only)