Fixing up and handling a lot of circular dependency imports in scenery, and adding svgns/xlinkns for namespaces. See https://github.com/phetsims/chipper/issues/871
Fixing up and handling a lot of circular dependency imports in scenery, and adding svgns/xlinkns for namespaces. See https://github.com/phetsims/chipper/issues/871

phetsims/scenery,phetsims/scenery,phetsims/scenery