check out ian black's work

https://github.com/IanTBlack/br_sensors

1) Used TEOS-10 pressure to depth conversion to compute depth.
2) Changed variable/function names to more closely match MS5837-30BA manual.
3) Combined read and temperature/pressure/depth/altitude functions into one.
4) temperature/pressure/depth/altitude are called independently of one another. They do rely on one another, but I formatted in a way that doesn't require users to call pressure before calling depth.
5) absolute_pressure() give the absolute pressure reading in user selected units
6) pressure() removes atmospheric pressure if given. if not it uses standard atmospheric pressure.