fix the bouncing ascent (Calculate mode)

[eianlei]

In some dive profiles the deco/ascent is bouncing. The state machine exits deco state too early, and starts a tiny ascent step. Then ceiling is immediately reached and the state bounces back to deco. This can be seen as tiny peaks in the profile. Enhance the checking of ceiling.

[eianlei]

example case: bottom 55 meters, 20 min, you see bounce at 27 meters.
Issue occurs because ascent may go too fast beyond a potential deco stop.
Quick and dirty fix is to check that ascent cannot increment above ceiling. Add checks to statemachine checks of DivePhase.ASC_T and DivePhase.ASCENDING. Printing to console some debug messages.
TODO: add a debug window to the app, instead of using print to console.

Example:
if (beginDepth - stepAscend) < model.leadCeilingStop:
print('ASC_T bounce stop at {} m, runtime {}, index {}'
.format(model.leadCeilingStop, runtime, index))
endDepth = model.leadCeilingStop
else:
endDepth = beginDepth - stepAscend