Document how to set up UPnP in a non-blocking manner
Document how to set up UPnP in a non-blocking manner

(cherry picked from commit f4bebc272c560b025b47aa79ced156e18195d586)

ex/godot,ex/godot,ex/godot,ex/godot,ex/godot,ex/godot,ex/godot,ex/godot