Port over "joint wraparound" to joint_trajectory_controller

As impemented in [ROS Control 1](https://github.com/ros-controls/ros_controllers/blob/melodic-devel/joint_trajectory_controller/include/joint_trajectory_controller/init_joint_trajectory.h#L161)

I believe https://github.com/ros-controls/ros2_controllers/issues/84 needs to be implemented first or alongside this.