InverseKinTraj inheirits from NPWConstraintObjects

Kinsol caching and other things that were previously in
NonlinearProgramWithKinsol have been moved over. testIKtraj passes.
InverseKin now inheirits from NPWConstraintObjects

There's a fair amount of code duplication between InverseKin and
InverseKinTraj now, but this does get testIK working again.
Update RBConstraints for new constraint hierarchy
Merge pull request #2 from avalenzu/trajopt

InverseKin and RigidBodyConstraint updates