multi: add new config peer-msg-rate-bytes

sample-lnd.conf

@@ -1814,6 +1814,13 @@
 ;
 ; gossip.ban-threshold=100
 
+; The peer-specific rate of outbound gossip messages, expressed in bytes per
+; second. This setting controls the long-term average speed of gossip traffic
+; sent from your node. The rate limit is applied to each peer. If the rate of
+; outgoing messages exceeds this value, lnd will start to queue and delay
+; messages sending to that peer to stay within the limit.
+; gossip.peer-msg-rate-bytes=51200
+
 [invoices]
 
 ; If a hold invoice has accepted htlcs that reach their expiry height and are