Merge branch 'develop' of ssh://labs.etsi.org:29419/arf/world-analysis-api-helpers/unity-world-analysis-arfoundation-wrapper-package into HEAD

Fix a bug in the trackable selection algorithm.
Change the way ARAnchorManager is used in the ARCoreAnchors module

File download safe multiple download at the same time, prevent images from the same url to be downloaded several times

WA now supports multiple trackable modules, add module mesh for iOS, capability are sent by module, moved prefab for arfoundation manager in resources folders