Streaming context metrics at table level [DBZ-2651]

Migrated from [DBZ-2651](https://issues.redhat.com/browse/DBZ-2651)

Hi, 
 
I am using [https://github.com/debezium/debezium-examples/tree/master/monitoring] , and I would like to have debezium_metrics_MilliSecondsSinceLastEvent or debezium_metrics_TotalNumberOfEventsSeen for streaming context at table level, that is, not just at connector level. Such as for example, there is debezium_metrics_RowsScanned for snapshot context at table level. Is it possible?
 
Thanks, 
Hrvoje

Read the monitoring example linked in the issue and compare the existing table-level RowsScanned metric with the connector-level streaming metrics named here. Trace how snapshot and streaming contexts expose metrics; done means MilliSecondsSinceLastEvent or TotalNumberOfEventsSeen is available at table level with suitable coverage and documentation.

Written by the indexing model from the issue text.