Add "description" to list of fields that MAY be included in stream creation #186
Description
In section 7.1.1.1, we say that the stream creation request MAY include any Receiver-supplied fields, and then we list events_requested and delivery. We should either include description as well, or remove the list and let implementers discover which fields are Receiver-supplied above in section 7.1.1 (the latter option being more future-proof if we add any other Receiver-supplied fields in later versions).