[actuator] Introduce ArUco Marker

The ArUco marker is an AR-Marker that allows to compute the camera pose
from images in the ‘real world’.
The purpose of this actuator is to provide a virtual instance of such a
marker in MORSE. By adding an ArUco marker to a MORSE simulation, you can
subsequently stream/export a (virtual) camera image and eventually use
an AR Marker without a physical camera setup or, i.e, test algorithms or
simulate visual servoring.
[doc] Document the addition of arucomarker