Commit kafka reads once the item was persisted

In order to continue using the Kafka High Consumer API, the disruptor
was removed. This allows a direct call to to kafka to commit the offsets
when items are flushed.

Different ConsumerConnectors had to be created for Metrics and Alarms
so the offsets could be committed separately

Changed configuration to match the new model.  Remove configuration
parameters that were no longer needed

Changed the name Disruptor to Pipeline

Allow only one EventHandler per pipeline

Added code to flush the Metrics and Alarms, and shutdown the Kafka ConsumerConnections on a normal shutdown. This keeps the persister from losing Metrics and Alarms.

Made measurementTimeStampSimpleDateFormat not static since SimpleDateFormat is not thread safe

Changed some logging debug statements so Strings weren't created if debug not on

Created FlushableHandler as a base class and moved duplicate code into it from MetricHandler and AlarmStateTransitionHistoryHandler

Change-Id: Id31a1d148f8e796f5be483dd02544be49c009b18

Changed MetricHandler to take MetricEnvelope[]

Change-Id: Ifabbe253cc0163f150ada2252a41a5d9fb9ab423