[feat] Add AttitudeQuaternion coordinate subset "addition" and "subtraction" #511
Description
Is your feature request related to a problem? Please describe.
Add the ability to properly combine the AttitudeQuaternion coordinate subset, since regular addition of an attitude quaternion does not make sense.
Describe the solution you'd like
Override the CoordinateSubset.add method in the AttitudeQuaternion class to get it to multiply the quaternions (representing a composite rotation of the first followed by the second), and override the CoordinateSubset.subtract method to get it to divide the quaternions (representing a relative rotation between two quaternions)