Attempt to make default config more consistent

The general idea here is that config examples should just have a hash and no
extraneous whitespace, both to make it easier for people who don't understand
yaml, and to make the examples stand out from the comments.

synapse/config/ratelimiting.py

@@ -32,27 +32,34 @@ class RatelimitConfig(Config):
         ## Ratelimiting ##
 
         # Number of messages a client can send per second
+        #
         rc_messages_per_second: 0.2
 
         # Number of message a client can send before being throttled
+        #
         rc_message_burst_count: 10.0
 
         # The federation window size in milliseconds
+        #
         federation_rc_window_size: 1000
 
         # The number of federation requests from a single server in a window
         # before the server will delay processing the request.
+        #
         federation_rc_sleep_limit: 10
 
         # The duration in milliseconds to delay processing events from
         # remote servers by if they go over the sleep limit.
+        #
         federation_rc_sleep_delay: 500
 
         # The maximum number of concurrent federation requests allowed
         # from a single server
+        #
         federation_rc_reject_limit: 50
 
         # The number of federation requests to concurrently process from a
         # single server
+        #
         federation_rc_concurrent: 3
         """