s/timeline/event graph

Author: turt2live

specification/server_server_api.rst

@@ -900,8 +900,8 @@ Receipts
 --------
 
 Receipts are EDUs used to communicate a marker for a given event. Currently the
-only kind of receipt supported is a "read receipt", or where in the timeline a
-user has read up to.
+only kind of receipt supported is a "read receipt", or where in the event graph
+the user has read up to.
 
 Read receipts for events events that a user sent do not need to be sent. It is
 implied that by sending the event the user has read up to the event.