database config is not kept in separate config file anymore

docs/postgres.rst

@@ -34,19 +34,15 @@ Synapse config
 When you are ready to start using PostgreSQL, add the following line to your
 config file::
 
-    database_config: <db_config_file>
-
-Where ``<db_config_file>`` is the file name that points to a yaml file of the
-following form::
-
-    name: psycopg2
-    args:
-        user: <user>
-        password: <pass>
-        database: <db>
-        host: <host>
-        cp_min: 5
-        cp_max: 10
+    database:
+        name: psycopg2
+        args:
+            user: <user>
+            password: <pass>
+            database: <db>
+            host: <host>
+            cp_min: 5
+            cp_max: 10
 
 All key, values in ``args`` are passed to the ``psycopg2.connect(..)``
 function, except keys beginning with ``cp_``, which are consumed by the twisted