Fix typo in connecting ui.descRate to setDescRate

Qt didn't find the right function without the type there. This also gets
rid of the warning about that.

Signed-off-by: Anton Lundin <glance@acc.umu.se>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Connect prefs.descrate to drop_stone_mode points

This enables so we can change the decent speed for drop like a stone
mode.

Signed-off-by: Anton Lundin <glance@acc.umu.se>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Make pO2 settings functional in planner

Spin boxes for pO2 are now hooked up to preference values. Adding new
cylinders (or changing their fo2) computes the MOD accordin to the current
value of decopo2. Note that chaning the limits for deco pO2 does _not_
automatically update the switch depth of all cylinders as those might have
been manually entered.

Furthermore, MOD has now to option of rounding to multiples of a given
depth. That is used for the automatic switch depth which are now always
multiples of 3m (so that EAN50 is switched to at 21m rather than 22m).

Signed-off-by: Robert C. Helling <helling@atdotde.de>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Make gas mod be reasonable for users of imperial units as well

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Fix keyboard shortcuts for user manual

Shortcuts for widgets without focus should have window context.

Signed-off-by: Sergey Starosek <sergey.starosek@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>