Lots of changes in the inelastic cohesive set of classes.
- correct a lot of bugs and comment the inelastic cohesive law : pkg/dem/Law2_ScGeom6D_InelastCohFrictPhys_CohesionMoment
- change some variables names and comments : pkg/dem/InelastCohFrictMat pkg/dem/InelastCohFrictPhys pkg/dem/Ip2_2xInelastCohFrictMat_InelastCohFrictPhys