preview 10

• hub is more robust to odd master-behaviour (lazy timings and subsequent resets)
• prepare new timing-method which will replace the old one in the next couple of weeks (a 6µs millis() call at 8MHz is not suitable for OW)
• cleanup send / receive / waitForTimeslot to react faster to bus (better for µC with less than 16 MHz)
• support for skipROM-cmd if only one slave is present (thanks to Giermann)
• speed up atmel-crc-functions
• tested with DS9490R: ds28b20, ds2401, ds2405, ds2413, more will follow