Draft: Added draft of Hoek Brown with orthotropy and three orthogonal joint sets.
This is an untested implementation of HoekBrown with orthotropic elasticity and three orthogonal joint sets.
@gerasimov ready for testing -- it's best to do the test from Ismael's paper both in 2D and in 3D. Basic setup in the script I sent you as a link.
@kuateric This might require some polishing but should be roughly fine.
Also note: testing is important because fourth-order tensor access changed in MFront a while ago. Hence 2D and 3D Testing are both important.