Removed STM module. See #1503

* Removed from build. Didn't remove akka-stm directory, contains transactors also.
* Replaced usage of org.multiverse.api.latches.StandardLatch in some tests with testkit.TestLatch

akka-docs/scala/code/StmDocSpec.scala

@@ -1,27 +0,0 @@
-package akka.docs.stm
-
-import org.scalatest.WordSpec
-import org.scalatest.matchers.MustMatchers
-
-class StmDocSpec extends WordSpec with MustMatchers {
-
-  "simple counter example" in {
-    //#simple
-    import akka.stm._
-
-    val ref = Ref(0)
-
-    def counter = atomic {
-      ref alter (_ + 1)
-    }
-
-    counter
-    // -> 1
-
-    counter
-    // -> 2
-    //#simple
-
-    ref.get must be === 2
-  }
-}

akka-docs/scala/index.rst

@@ -12,7 +12,6 @@ Scala API
    futures
    dataflow
    agents
-   stm
    transactors
    fault-tolerance
    dispatchers

akka-docs/scala/transactors.rst

@@ -0,0 +1,6 @@
+.. _transactors-scala:
+
+Transactors (Scala)
+===================
+
+The Akka Transactors module has not been migrated to Akka 2.0-SNAPSHOT yet.