* Added Math.Net Numerics for vector and linear algebra calculations. * Fixed bug where uncaught exception could occur when EffectiveStress was calculated during validation. * Improved PipingSurfaceLineCreator to project the 3D world coordinates onto the LZ plane for the kernel. * Introduced Point2D ** Has - operator overload to derive vector from 2 points. Related to Issue [WTI-21] git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@449 5a3db67b-de53-47b5-99c8-a1c30a6650e2