Graphite: Support tags

Add support for tags in Graphite reporter.
See README for additional information.

Jest

Use jest instead of Mocha for tests

Bug fix: reporting default tags in DataDog reporter

Merge pull request #19 from ysa23/fix/datadog-default-tags

Bug fix - reporting default tags

DataDog: batch metrics reporting

Using a single socket to report to Datadog, and buffering the messages to send in batches

Fix error handling

v0.7.0

0.7.0

Minor: update README

v0.6.1

0.6.1

Add DataDog reporter

v0.6.0

0.6.0

Metrics-JS

Re-release of metrics-js - an abstraction for metrics reporting, agnostic of aggregator.
Currently supports graphite