adding datadog reporter, and removing unecessary markdown links

README.md

@@ -146,8 +146,9 @@ Publishing Metrics
 
 Clients are available for the following destinations:
 
-* Librato - [https://github.com/mihasya/go-metrics-librato](https://github.com/mihasya/go-metrics-librato)
-* Graphite - [https://github.com/cyberdelia/go-metrics-graphite](https://github.com/cyberdelia/go-metrics-graphite)
-* InfluxDB - [https://github.com/vrischmann/go-metrics-influxdb](https://github.com/vrischmann/go-metrics-influxdb)
-* Ganglia - [https://github.com/appscode/metlia](https://github.com/appscode/metlia)
-* Prometheus - [https://github.com/deathowl/go-metrics-prometheus](https://github.com/deathowl/go-metrics-prometheus)
+* Librato - https://github.com/mihasya/go-metrics-librato
+* Graphite - https://github.com/cyberdelia/go-metrics-graphite
+* InfluxDB - https://github.com/vrischmann/go-metrics-influxdb
+* Ganglia - https://github.com/appscode/metlia
+* Prometheus - https://github.com/deathowl/go-metrics-prometheus
+* DataDog - https://github.com/syntaqx/go-metrics-datadog