OrientationConstraint
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Definition::

    # PositionConstraint message base_navigation
    
    string                      frame
    geometry_msgs/Point         look_at
    float64                     angle_offset
    
    # frame: the coordinate frame in which the orientation constraint is active
    #
    #  - examples:  "map", "person" , "table"
    
    # angle: goal yaw of the robot
    #
    #  - example:   (0.2,0.5)
    
    # look_at: point in the selected coordinate frame (x,y) the robot should ook at
    #
    #  - example:   (0.2,0.5)
    
    # NOTE: if both yaw and look at are set, the yaw is chosen