Limit the scope of gasidx in add_plan_to_notes

Signed-off-by: Anton Lundin <glance@acc.umu.se>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Use user entered pO2 limits for high pO2 warnings.

Furthermore, replaced gasmix accessors instead of .permille directly (think: air!)

Signed-off-by: Robert C. Helling <helling@atdotde.de>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>