Add Distribution Support to SemanticAggregatorMetric

[ao2017]

Heroic histogram data is currently computed locally.
It is practically impossible to aggregate percentile.
We are adding distribution to heroic to address that issue. Distribution will create data sketch that will be used upstream to compute percentile on the entire data distribution.

This task will add distribution support to Semantic Metric Aggregator.

DoD: Ensure that distribution is supported in remote metric.

Code Pointer:
https://github.com/spotify/semantic-metrics/blob/master/remote/src/main/java/com/spotify/metrics/remote/SemanticAggregatorMetricRegistry.java