posix: Add SockAddrIn6, In6Addr and inet_pton
posix: Add SockAddrIn6, In6Addr and inet_pton

Fixes bug 670492.

frida/vala,rvu95/vala,flobrosch/vala-fixes,jessevdk/vala,severinh/vala,spidermonkdust/vala,GNOME/vala,GNOME/vala,playya/vala,tjol/vala-tjol,flobrosch/vala-fixes,GNOME/vala,frida/vala,tjol/vala-tjol,jessevdk/vala,Distrotech/vala,playya/vala,frida/vala,spidermonkdust/vala,xdave/pvala,rvu95/vala,spidermonkdust/vala,tjol/vala-tjol,frida/vala,severinh/vala,frida/vala,GNOME/vala,playya/vala,jessevdk/vala,flobrosch/vala-fixes,Distrotech/vala,rvu95/vala,Distrotech/vala,severinh/vala