Netgen 2D and 3D hypotheses

Netgen 2D and Netgen 3D hypotheses work only with Netgen 1D-2D and Netgen 1D-2D-3D algorithms. These algorithms do not require definition of lower-level  hypotheses and algorithms (2D and 1D for meshing 3D objects and 1D for meshing 2D objects). They prove to be useful if lower-level meshing is homogeneous for all wires and faces of the meshed object.