New in version 1.1.
Move parentage and spanners from donors to recipients.
Give everything from donors to recipients. Almost exactly the same as container setitem logic. This helper works with orphan donors. Container setitem logic can not work with orphan donors. Return donors.
Changed in version 2.0: renamed scoretools.bequeath() to componenttools.move_parentage_and_spanners_from_components_to_components().