Publish controller and application specific metrics

[Adityashar]

Is your feature request related to a problem? Please describe.
We are making use of kubernetes-replicator on our Kubernetes platform and we need to set up SLOs based on the metrics generated by this application. However, currently no metrics are published by the same.

Describe the solution you'd like
Simple controller metrics such as controller_runtime_reconcile_total and controller_runtime_reconcile_errors_total.
Along with these, maybe application functionality based metrics as well such replication_count_total and replication_errors_total with labels such as kind, resource_name etc

[wirwolf]

Hello. Also interesting this feature