Spat external for OM# v3.5

• Updated for Spat 5.2
• Fix speakers position setup in spat-scene editor
• Updates help patches

Requires Spat installation
See: https://forum.ircam.fr/projects/detail/spat/

Also requires the "odot" OM# external:
https://github.com/cac-t-u-s/o.OM/releases/tag/v1.0