Float zero comparison in CFM arrival estimation

[m-kro]

Replaces the direct floating point comparison to 0 inside the CFM arrival estimation with a check against NUMERICAL_EPS.
Signed-off-by: m-kro m.barthauer@t-online.de

[behrisch]

@m-kro Do you have a small example where it makes a difference?

[m-kro]

This is connected to the ongoing corrections in the SSM device, where the CFM arrival estimation is used. I actually had trouble with a very very small acceleration value. I will need some time to compile a working example.

[behrisch]

Thanks, it would be great to have one.

[m-kro]

Ok I have found the simulation where I discovered this. It is the one from issue #5527 (initial post) using seed 27. At time 2402.2, the assertion eInfo.foeEstimatedConflictEntryTime > 0. is triggered for the conflict ego "Pkw.28.8" vs. foe "Pkw.32.45". eInfo.foeEstimatedConflictEntryTime is the outcome of the CFM arrival time estimation.

[namdre]

I was unable to reproduce the assertion. However, the change looks reasonable enough and does not break any tests so I'm merging it anyway.