Include enumerations in extensible protocol elements (#1799)

An extension can make e.g. a new filter type.

Author: ianswett

draft-ietf-moq-transport.md

@@ -970,7 +970,7 @@ specific to the underlying transport protocol usage (see {{session}}).
 
 Endpoints use the exchange of Setup messages to negotiate MOQT extensions.
 Extensions can define new Message types, new Parameters, new Properties,
-or new framing for Streams and Datagrams.
+new Parameter values, or new framing for Streams and Datagrams.
 
 The client and server MUST include all Setup Options {{setup-options}}
 required for the negotiated MOQT version in SETUP.