update docs for new metrics

Author: reshmabidikar

userguide/aviate/aviate-health.adoc

@@ -108,13 +108,17 @@ The following table lists these metrics:
 
 |queue.bus.late
 |This is a counter that shows how many unprocessed bus events we have at time 't'. This number should be close to 0.
+|queue.bus.ext.late
+|This is a counter that shows how many unprocessed external bus events we have at time 't'. This number should be close to 0.
 
 |queue.bus.incoming
 |The is rate of incoming bus events at time t. The default granularity is `MINUTE` but results can be aggregated based on the `granularity` query parameter - e.g hourly incoming rate.
-
+|queue.bus.ext.incoming
+|The is rate of incoming external bus events at time t. The default granularity is `MINUTE` but results can be aggregated based on the `granularity` query parameter - e.g hourly incoming rate.
 |queue.bus.processing
 |This is an estimation of the time in mSec that was used to process the bus event. These values may become incorrect once we have late bus entries.
-
+|queue.bus.ext.processing
+|This is an estimation of the time in mSec that was used to process the external bus event. These values may become incorrect once we have late bus entries.
 |queue.notifications.late
 |This is a counter that shows how many unprocessed notifications we have at time 't'. This number should be close to 0.