New feature: do not show sensor customviews when no sensors attached There are mCCR divers, that use a DC just for deco and time purposes and not for O2 tracking and logging. These divers typically use the existing Fixed SP mode, and have 0 active 02 sensors. This commit simply suppresses display of the 2 customviews in case there are no active sensors defined. Signed-off-by: Jan Mulder <jlmulder@xs4all.nl>