ACLs would not work, as evidenced by #311.

Add a log message for unknown sa_families, and use memmove to extract
the sa_family member of the sockaddr into a suitably sized variable.

Diagnosed by:	Mithrandir
Fixes:	#311


git-svn-id: http://www.varnish-cache.org/svn/trunk@3171 d4fa192b-c00b-0410-8231-f00ffab90ce4