Switch to using a Librato aggregator instead of a queue
Switch to using a Librato aggregator instead of a queue

From their docs (https://github.com/librato/librato-metrics#aggregate-measurements)
seems like this may be more appropriate for the kind of usage we have
here.

Also enable automatic submission based on count and tune it via
`LIBRATO_AUTOSUBMIT_COUNT`.

ello/kinesis-stream-reader