Inaccuracies when defining a wing cell border using ribs and spars

[joergbrech]

The lax tolerances here:

tigl/src/wing/CCPACSWingCell.cpp

Lines 893 to 896 in f20dcb7

	TrimSpanwise(cache, SpanWiseBorder::Inner, m_positioningInnerBorder, 1e-2);
	TrimSpanwise(cache, SpanWiseBorder::Outer, m_positioningOuterBorder, 1e-2);
	TrimChordwise(cache, ChordWiseBorder::LE, m_positioningLeadingEdge, 1e-2);
	TrimChordwise(cache, ChordWiseBorder::TE, m_positioningTrailingEdge, 1e-2);

lead to false positives, when the functions internally try to determine if the cell borders can be calculated by trimming a curve instead of using Boolean operations. This leads to inaccurate results.

It is very hard to decide on a good tolerance here and this is somewhat related to the monster #756, but for sure the tolerances have to be stricer than 1e-2.