Draft: Attempt to exclude joints >2 for collisions

Attempt to exclude joints >2 for collisions based on :param update_home_collisions: If False, the visual and collision geometries will not be updated, meaning this joint will neither be plotted nor considered for collision checking until done so. Useful for either building models that don't need either of these features or when adding multiple joints, so this can be done after the last only.

in _add_joint