Spring Boot sample with Open TSDB export for metrics.

Start opentsdb, e.g. with [Docker Compose]()

[source,indent=0]
----
$ docker-compose up
----

Run the app and ping the home page (http://localhost:8080) a few times. Go and look at
the result in the TDB UI, e.g.

[source,indent=0]
----
	$ curl localhost:4242/api/query?start=1h-ago&m=max:counter.status.200.root
	[
  		{
    		"metric": "counter.status.200.root",
    		"tags": {
      			"prefix": "spring.b968a76"
    		},
    		"aggregateTags": [],
    		"dps": {
      			"1430492872": 2,
      			"1430492875": 6
    		}
  		}
	]
----