Various doc fixes and improvements

docs/features/experimental/application-service.md

@@ -26,7 +26,7 @@ synapseSql:
   connection: '<DB CONNECTION URL>'
 ```
 
-The `synapseSql` section is used to retrieve display names which are not directly accessible in this mode.
+The `synapseSql` section is optional. It is used to retrieve display names which are not directly accessible in this mode.
 For details about `type` and `connection`, see the [relevant documentation](../../stores/synapse.md).
 If you do not configure it, some placeholders will not be available in the notification, like the Room name.
 

docs/features/federation.md

@@ -46,15 +46,6 @@ lookup:
 invite:
   resolution:
     recursive: false
-session:
-  policy:
-    validation:
-      forLocal:
-        toRemote:
-          enabled: false
-      forRemote:
-        toRemote:
-          enabled: false
 ``` 
 
 There is currently no way to selectively disable federation towards specific servers, but this feature is planned.

docs/features/identity.md

@@ -1,6 +1,4 @@
 # Identity
-**WARNING**: This document is incomplete and can be misleading.
-
 Implementation of the [Identity Service API r0.1.0](https://matrix.org/docs/spec/identity_service/r0.1.0.html).
 
 ## Lookups