Per design in YARN-2928, implement NM writing container lifecycle events and container system metrics to ATS.
[Collector wireup] Set up timeline collector with basic request serving structure and lifecycle
[Collector wireup] Implement timeline app-level collector service discovery
[Data Model] Make putEntities operation be aware of the app's context
[Data Model] create overall data objects of TS next gen
[Data Model] Create ATS metrics API
[Event Producers] NM TimelineClient container metrics posting to new timeline service.