=act,tes Initial draft of internal MetricsKit

Note: This is NOT aimed to provide an micro-benchmarking solution.
The goal is to provide data for broad trend analysis. For techniques
that fight the inliner and other specialised techniques, refer to JMH.

+ custom console and graphite reporters
  - had to be custom because it's not possible to add custom metric
    types to the existing reporters
+ initial hdr.Histogram histogram() provider, see
  http://latencyutils.github.io/LatencyUtils/
+ Not using timers provided by Metrics, instead use the above histogram
+ Added average Actor size measurement
+ Measuring the "blocking time" when an actor is created, before we fire
  of the async part of this process; Measures in loop and will fluctuate
  a lot. Times are in `us` -- System.nanoTime should provide good enough
  resolution.
+ Measuring total actor creation time by using
  `KnownOpsInTimespanTimer`, which given a known number of ops, in a
  large amount of time, roughtly estimates time per one operation.
  // Yes, we are aware of the possibility of GC pauses and other horrors
+ All classes are `private[akka]`, we should not encourage people to use
  this yet
+ Counters use Java 8's `LongAdder`, which is metric's private;
  The new trend in Java land will be copy paste-ing this class ;)
+ Metrics are logged to Graphite, so we can long-term analyse these
+ Reporters are configurable using typesafe-config

! I'm not very happy about how I work around Metrics not being too open
  for adding additional custom metrics. Seems like a hack at places.
  I will consider removing the Metrics dependency all together.
  numbers

Example output:

```
-- KnownOpsInTimespanTimer-------------------------------------------
  actor-creation.total.creating-100000-actors.Props|new-EmptyArgsActor|…||-same
               ops = 100000
              time = 1.969 s
             ops/s = 50782.22
               avg = 19.69 μs

-- AveragingGauge---------------------------------------------------
  actor-creation.Props|new-EmptyArgsActor|…||-same.avg-mem-per-actor
                avg = 439.67
```

project/TestExtras.scala

@@ -117,7 +117,7 @@ object TestExtras {
 
   object StatsDMetrics {
 
-    val statsd = config("statsd") extend Test
+    val statsd = config("statsd")
 
     val enabled = settingKey[Boolean]("Set to true when you want to send stats to statsd; Enable with `-Dakka.sbt.statsd=true`")
 
@@ -128,7 +128,6 @@ object TestExtras {
     val port = settingKey[Int]("Port on which statsd is listening, defaults to 8125")
 
 
-
     val settings = Seq(
       // configuration
       enabled in statsd := sys.props("akka.sbt.statsd") == "true",
@@ -202,9 +201,9 @@ object TestExtras {
 
       private def testTimerKey(det: Event): String = s"${det.fullyQualifiedName}.${testSelectorToId(det.selector)}"
 
-      private def testSelectorToId(sel: testing.Selector): String = sel.asInstanceOf[TestSelector].testName().replaceAll("""[^\w]""", "_")
+      private def testSelectorToId(sel: testing.Selector): String = sanitize(sel.asInstanceOf[TestSelector].testName())
 
-      private def testCounterKey(det: Event, status: Status): String = s"${det.fullyQualifiedName}.${status.toString.toLowerCase}"
+      private def testCounterKey(det: Event, status: Status): String = s"${sanitize(det.fullyQualifiedName)}.${status.toString.toLowerCase}"
 
       private def keySuccess(fullyQualifiedName: String): String = fullyQualifiedName + ".success"
 
@@ -212,6 +211,8 @@ object TestExtras {
 
       private def keyError(fullyQualifiedName: String): String = fullyQualifiedName + ".error"
 
+      private def sanitize(s: String): String = s.replaceAll("""[^\w]""", "_")
+
     }
 
   }