The code for loading the .ele and .node TetGen files was potentially buggy because using uninitialized variable.
The improved ChNodeBody class (the constraint between a ChNodeFEMxyz and a ChBody)  has been moved in unit_FEM.
It uses shared pointers for storing the node, whereas before it used a pointer to the mesh plus an index, for the same purpose. The new approach is more flexible and easy to manage.
A new Initialize method() is introduced too, and the old is kept for backward compability.