The Divesoft Liberty has four O2 sensors. So far, we had a hard coded
limit of three sensors and crashed with a failed assert when we
encoutered more than three. This allows for up to
MAX_O2_SENSORS which is currently 6. The voting logic is adapted
accordingly: We sort the values and we keep deleting the values that
differ more than 20% by value from the closest. This follows what
Shearwater implements on their computers.
In some of the import/export functions the value is still hard
coded to 6 thanks to explicit field names.
Signed-off-by: Robert C. Helling <helling@lmu.de>
