Integrate with Metrics for various stats collection

As suggested by ianeboston in OAK-3478 current approach of collecting TimeSeries data is not easily consumable by other monitoring systems. Also just extracting the last moment data and exposing it in simple form would not be useful.

Instead of that we should look into using Metrics library [1] for collecting metrics. To avoid having dependency on Metrics API all over in Oak we can come up with minimal interfaces which can be used in Oak and then provide an implementation backed by Metric.

This task is meant to explore that aspect and come up with proposed changes to see if its feasible to make this change

• metrics-core ~100KB in size with no dependency
• ASL Licensee

[1] http://metrics.dropwizard.io