matrix-spec-proposals

b885714d - Remove the "required" designation from the `url` field of certain

Remove the "required" designation from the `url` field of certain m.room.message msgtypes. Now that content referenced by the *m.audio*, *m.file*, *m.image*, and *m.video* message types can be encrypted, the `url` field is required *only* if the content is unencrypted. The "required" designation in the event schemas (which prefixes the field description with "Required" in bold in the generated HTML) is used to indicate fields which must always be present, and this is no longer the case. Signed-off-by: Jimmy Cuadra <jimmy@jimmycuadra.com>