examples/posix_sockets: parse ipv6 interface id
examples/posix_sockets: parse ipv6 interface id

jasonatran/RIOT,kaspar030/RIOT,miri64/RIOT,basilfx/RIOT,jasonatran/RIOT,ant9000/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,RIOT-OS/RIOT,ant9000/RIOT,jasonatran/RIOT,kaspar030/RIOT,OlegHahm/RIOT,miri64/RIOT,kYc0o/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,OlegHahm/RIOT,kYc0o/RIOT,basilfx/RIOT,OTAkeys/RIOT,OTAkeys/RIOT,authmillenon/RIOT,kYc0o/RIOT,OTAkeys/RIOT,RIOT-OS/RIOT,kaspar030/RIOT,miri64/RIOT,OlegHahm/RIOT,OlegHahm/RIOT,kYc0o/RIOT,OTAkeys/RIOT,jasonatran/RIOT,basilfx/RIOT,ant9000/RIOT,authmillenon/RIOT,ant9000/RIOT,OTAkeys/RIOT,miri64/RIOT,authmillenon/RIOT,kaspar030/RIOT,basilfx/RIOT,kaspar030/RIOT,miri64/RIOT,ant9000/RIOT,kYc0o/RIOT,basilfx/RIOT,jasonatran/RIOT,OlegHahm/RIOT