nanocoap: provide Accept option convenience function
nanocoap: provide Accept option convenience function

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