Modifying code comments in ScGeom, now that it may apply to sthg else than Sphere and Facet shapes

Jérôme Duriezrequested to merge
codeComment into master

That code comment in a part of ScGeom::getIncidentVel suggested (probably because it was written at a time only Sphere and Facet shapes could be thought of) sthg could be wrong when using LevelSet, while it is not the case.

I'm thus modifying it

Merge request reports