Add Fem3d frictionless contact
Merge branch 'tmp/fem3dFrictionlessContact' into feature/fem3d-frictionlessContact
fem3d representation contact, minor changes to formatting
Add fem3d representation contact unit tests
Update 3d tetrahedron element, remove state from constructor

- Move portions of the constructing routines to the initialize function,
following the same design as fem1d beam.
- Update the tests
Minor fix, update constructor in example fem3d
Adds functions to set the velocities for a RigidRepresentation.

Since the velocities are used in free motion to update the pose of a
RigidRepresentation; with these functions a Behavior can exactly control
the next pose.  Note that setPose is non-functional for
RigidRepresentations, and making it functional would be incorrect
because then any residual velocity would cause the representation to
move away from the pose in the free motion step.

Currently this is being used in a side project to move the
representation of a tool to the pose being received from an
InputComponent.
Minor fix, keep usage documentation in fem 3d tetrahedron constructor
minor fix, fem 3d tetrahedron unit test, update initialization

- Use preset parameters for initialization function
fem 3d contact test, remove tetrahedron testing

- Tetrahedron functions should be verified in tetrahedron unit test.
fem 3d contact test, modify testing formatting

- Introduce new function for testing eigen matrices, which prints out
data on their differences.  Indicates whether they have different
dimensions, whether their normed difference is significantly different,
and if they are vectors which values are different.
fem 3d contact, bug fix

- We currently assume implicit integration in the contacts, so we should
include a factor of dt in H.
Merge branch 'feature/set-velocities-rigidrepresentation' into 'master'

Adds functions to set the velocities for a RigidRepresentation.

+1: Vien Tran, Harald Scheirich, gsathyaseelan

Merged-on: https://www.assembla.com/code/OpenSurgSim/git/merge_requests/726773
Merge branch 'master' into feature/fem3d-frictionlessContact
Merge branch 'feature/fem3d-frictionlessContact' into 'master'

Add fem3d frictionless contact

Merged-on: https://www.assembla.com/code/OpenSurgSim/git/merge_requests/717253
fem3d tetrahedron, minor fix.  Update documentation
Merge branch 'master' into feature/fem3d-tetrahedron-update-constructor
Fix merge related compilation error in fem3d tetrahedron

- Updated usage of FemElement3DTetrahedron constructor to new signature.
Merge branch 'feature/fem3d-tetrahedron-update-constructor' into 'master'

Update fem3d tetrahedron constructor

Merged-on: https://www.assembla.com/code/OpenSurgSim/git/merge_requests/723043