Unlike the HISTOGRAM metric type, which aggregates on the Agent during
a given time interval, a DISTRIBUTION metric sends all the raw data
during a time interval to Datadog, and aggregations occur server-side.
Because the underlying data structure represents raw, unaggregated data,
distributions provide two major features:
Example of usage follows:
From the Datadog documentation:
https://docs.datadoghq.com/developers/metrics/types/?tab=distribution#definition
Closes #46