+ akka-cluster-metrics: new akka module

* new akka module split from akka-cluster
* provide sigar provisioning
* fix ewma usage
* resolve #16121
* see #16354

akka-cluster/src/multi-jvm/scala/akka/cluster/ClusterMetricsDisabledSpec.scala

@@ -4,6 +4,8 @@
 
 package akka.cluster
 
+// TODO remove metrics 
+
 import akka.remote.testkit.{ MultiNodeSpec, MultiNodeConfig }
 import com.typesafe.config.ConfigFactory
 import akka.testkit.LongRunningTest

akka-cluster/src/multi-jvm/scala/akka/cluster/ClusterMetricsSpec.scala

@@ -4,6 +4,8 @@
 
 package akka.cluster
 
+// TODO remove metrics 
+
 import scala.language.postfixOps
 import scala.concurrent.duration._
 import com.typesafe.config.ConfigFactory

akka-cluster/src/multi-jvm/scala/akka/cluster/MultiNodeClusterSpec.scala

@@ -3,6 +3,8 @@
  */
 package akka.cluster
 
+// TODO remove metrics
+
 import language.implicitConversions
 import org.scalatest.{ Suite, Outcome, Canceled }
 import org.scalatest.exceptions.TestCanceledException

akka-cluster/src/multi-jvm/scala/akka/cluster/StressSpec.scala

@@ -3,6 +3,9 @@
  */
 package akka.cluster
 
+// TODO remove metrics 
+// FIXME this test is not migrated to metrics extension 
+
 import language.postfixOps
 import scala.annotation.tailrec
 import scala.collection.immutable

akka-cluster/src/multi-jvm/scala/akka/cluster/routing/AdaptiveLoadBalancingRouterSpec.scala

@@ -4,6 +4,8 @@
 
 package akka.cluster.routing
 
+// TODO remove metrics 
+
 import language.postfixOps
 import java.lang.management.ManagementFactory
 import scala.concurrent.Await