False positives in check, if wing cells can be trimmed rather than cut.

[joergbrech]

TiGL tries to determine if the geometry of a wing cell can be calculated by trimming a surface rather than cutting it with Boolean operations for a better performance. Currently, this check often has false positives and the trimmed result is wrong. The trimming is currently disabled in da2d269 and we should either remove the check completely or change it to be more reliable.

This is related to da2d269 and #865.

[condoratberlin]

Currently I would prefer to remove the checks, because the current version leads to wrong cell shapes.

[joergbrech]

@condoratberlin thanks for the feedback. I will prepare a patch release of TiGL either this or next week where the checks are disabled. I will keep this issue open for documentation purposes. If there are no further issues with the disabled tests, we can remove the checks completely at a later stage (which would just be a refactoring of the source code, without any behavioral changes).