Initial commit of metric service reorg
Added unit tests for simple and stats metric service
Added custom query metric service.  Also added relevant javadocs to all metrics interfaces.  Finally removed buggy old implementation
Small refactor of the common classes of the metric service. Implemented base tests to help validate that a custom metric function meets the expected criteria for the custom metric store
Fixed some javadocs for metric service
Cleaned up poms
Small cleanup of comments and constants
Forgot to add a shutdown method to metrics service to cleanup writer.
Added license headers
Merge pull request #10 from eawagner/metricsReorg

Reorganized Metrics service