Integrate Principal Directions of Curvature Framework

[alexpron]

Aim

We could include the Principal Directions of Curvatures Analysis Framework introduced in https://www.nature.com/articles/s41598-021-87124-y.

Framework in a nutshell:

• calculate angle between the gradient of the Fielder vector and the principal directions of curvatures
• Fielder vector is the first non constatn eigen-function of the Laplace Beltrami operator applied to the mesh
• angle distribution comparison to uniform angle distribution using KullBack Lieber divergence

Remarks from @JulienLefevreMars :

We should be careful about what is the reference uniform angle distribution over a mesh.
Hence, we could consider doing random rotations over the mesh to see how the angles evolves

On a different level, we should spent extra care about the citations and authors involved.