OP-1149 fix low temperature compensation formula
OP-1149 Remove shifts as they can have bad behaviours for negative numbers.
Documents correction algorithms as described in ms5611 documentation
OP-1149 change POW2 as POW2(0) led to undefined results
Merge remote-tracking branch 'origin/amorale/OP-1149_baro_fixes_backport' into rel-14.01