[PATCH] Add a simple table-based otu-calculator

[Dirk Hohndel]

Anton Lundin <glance at acc.umu.se> writes:

> For dives where divecomputers haven't provided us with a maxCNS, we
> calculate our cns accumulated during that dive based on a simple table.

This doesn't take multiple dives into account at all.

According to http://www.therebreathersite.nl/04_Links/Downloads/cns.pdf
it is common practice to calculate a surface decay as exponential decay
with a half-time of 90 minutes. Which means that in typical boat diving
the CNS value from the previous dive will have significant impact on the
next dive.

/D