Add configs to make profile data more private (#9203)

Add off-by-default configuration settings to:
- disable putting an invitee's profile info in invite events
- disable profile lookup via federation

Signed-off-by: Andrew Ferrazzutti <fair@miscworks.net>

docs/sample_config.yaml

@@ -101,6 +101,14 @@ pid_file: DATADIR/homeserver.pid
 #
 #limit_profile_requests_to_users_who_share_rooms: true
 
+# Uncomment to prevent a user's profile data from being retrieved and
+# displayed in a room until they have joined it. By default, a user's
+# profile data is included in an invite event, regardless of the values
+# of the above two settings, and whether or not the users share a server.
+# Defaults to 'true'.
+#
+#include_profile_data_on_invite: false
+
 # If set to 'true', removes the need for authentication to access the server's
 # public rooms directory through the client API, meaning that anyone can
 # query the room directory. Defaults to 'false'.
@@ -699,6 +707,12 @@ acme:
 #  - matrix.org
 #  - example.com
 
+# Uncomment to disable profile lookup over federation. By default, the
+# Federation API allows other homeservers to obtain profile data of any user
+# on this homeserver. Defaults to 'true'.
+#
+#allow_profile_lookup_over_federation: false
+
 
 ## Caching ##