fix default argument logic and documentation
if only one argument then ub = lb
output q as well as pts
robustifying (and correcting) argument handling in constraint chain
support multiple root links
lots of fixes in ContactImplicitTrajOpt - on argument parsing, support having no contact constraints or no joint limits, update from NonlinearConstraint.  adds utility method to CoordinateFrame
handle active collision options
adds (failing) unit test for contact implicit trajectory optimization.
adds support for optimization of systems with no control inputs.
mat2cell to num2cell per andres' suggestion
fix from michael's code review
Merge pull request #261 from RussTedrake/contact_traj_opt

playing with contact trajectory optimization