mod_rest/apidemo: Serve yaml with a (non-standard) content-type There's no Standard from what I can tell, found this one somewhere. Serving as text/* might help some clients do something sensible like not treat it as a binary file, which it isn't.

This module discards typing notifications sent to a bare host JID,
preventing error replies to be sent. These errors are harmless but can
be annoying sometimes if your client shows them prominently.