(CFACT-86) Networking facts for solaris

This patch adds support for networking facts for solaris. This is patterned on
the bsd networking resolver. 

@kylog while there is some commonality, factoring it out is hard: I cant use the BSD as a parent, as it wont compile in solaris (different headers, different data-structures and different system calls (getifaddrs/ioctl)), and moving it up to posix may not be worth the effort, since it would need to be templatized, and I am not sure if the same would work for other posix systems like AIX and HPUX.