Protocol OWFS_DS18B20

Protocol OWFS_DS18B20 - 1 wire DS18B20 connected using OWFS (http://owfs.org), works with 1-wire master like DS2482-100 and DS2482-200

notes:
* the mounting path of OWFS is /mnt/1wire/
* the id of sensor can include big letters and should have "28." prefix for ex."28.1C2A93050000"