setPayload sets a payload used for effort compensation
 
    This method provides a way to dynamically specify a payload
    that gets used to calculate efforts to compensate for
    gravitational effects and joint accelerations.
 
    Specifying a payload has no effect on any other
    functionality.
 
    The 'Mass' argument (required) specifies the payload mass
    in [kg].
 
    The 'CoM' argument (parameter) specifies the distance from
    the output to the center of mass of the payload. If left
    unspecified, the default assumes that the payload is
    located at the output of the end effector.
 
    Example
        mass = 1; % [kg]
        com = [1 0 0]; % 1 [m] in x
        kin.setPayload(mass, 'CoM', com);