Combine State Waypoint with Joint and Cartesian Waypoint

[marip8]

We should consider moving the velocity, acceleration, and effort targets from the StateWaypoint class to the JointWaypoint and CartesianWaypoint, and remove the StateWaypoint. This will track more closely to the robot controller concept of a waypoint. Planners and other users of the waypoint classes can decide whether or not to use the information provided.