Add room version 11 (#1604)

* Remove duplicate words.

* Add information on room version 11.

* Note some event changes.

* Newsfragment

* Fix-up event schema.

* Apply suggestions from code review

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

* Fix 'new in this version'.

* Clarify creator field.

* Fix-up event format & examples.

* Move the Redactions section to the client section.

* Reference the sender instead of the creator.

* More links

* Even more links.

* Fix order of headers.

* Fix typos.

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

* Clarify description of creator.

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

* Clean-up intro paragraphs for redactions.

* Clean-up examples and language.

* Review comments.

* FIx-up markup tags.

---------

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

data/event-schemas/examples/m.room.create.yaml

@@ -3,8 +3,7 @@
   "type": "m.room.create",
   "state_key": "",
   "content": {
-    "creator": "@example:example.org",
-    "room_version": "1",
+    "room_version": "11",
     "m.federate": true,
     "predecessor": {
       "event_id": "$something:example.org",

data/event-schemas/examples/m.room.redaction.yaml

@@ -1,8 +1,8 @@
 {
   "$ref": "core/room_event.json",
   "type": "m.room.redaction",
-  "redacts": "$fukweghifu23:localhost",
   "content": {
+    "redacts": "$fukweghifu23:localhost",
     "reason": "Spamming"
   }
 }

data/event-schemas/schema/m.room.create.yaml

@@ -6,7 +6,9 @@ properties:
   content:
     properties:
       creator:
-        description: The `user_id` of the room creator. This is set by the homeserver.
+        description: |-
+          The `user_id` of the room creator. **Required** for, and only present in, room versions 1 - 10. Starting with
+          room version 11 the event `sender` should be used instead.
         type: string
       m.federate:
         description: Whether users on other servers can join this room. Defaults to `true` if key does not exist.
@@ -32,8 +34,6 @@ properties:
             type: string
             description: The event ID of the last known event in the old room.
         required: [room_id, event_id]
-    required:
-      - creator
     type: object
   state_key:
     description: A zero-length string.

data/event-schemas/schema/m.room.redaction.yaml

@@ -5,18 +5,19 @@ description: 'This event is created by the server to describe which event has be
 properties:
   content:
     properties:
+      redacts:
+        description: The event ID that was redacted. Required for, and present starting in, room version 11.
+        type: string
       reason:
         description: 'The reason for the redaction, if any.'
         type: string
     type: object
   redacts:
-    description: The event ID that was redacted.
+    description: Required for, and only present in, room versions 1 - 10. The event ID that was redacted.
     type: string
   type:
     enum:
       - m.room.redaction
     type: string
-required:
-  - redacts
 title: Redaction
 type: object