Raster values to mesh scalars

Rework MeshSurfaceExtraction::getSurfaceMesh

Added CMake option OGS_EIGEN_DYNAMIC for using dynamically allocated eigen matrices

Fix dynamically allocated shape matrices

now it is harder to use them incorrectly

Cleanups

Tests for AddLayerToMesh

[PL] Move up process' output. Split post and out.

The post() is split from result output as it is intended
for "after solve" procedures and not output.

Element flipping

[FileIO] GMSH

AddLayer properties