'git mv' rst resources to md

This is mainly intended to keep the git history as neat as possible.
No actual conversion yet, so now both the rst and the paradox docs
are broken, which will be fixed in the next commits.

akka-docs/src/main/paradox/scala/code/docs/stream/QuickStartDocSpec.scala

@@ -0,0 +1,88 @@
+/**
+ * Copyright (C) 2016-2017 Lightbend Inc. <http://www.lightbend.com>
+ */
+package docs.stream
+
+//#stream-imports
+import akka.stream._
+import akka.stream.scaladsl._
+//#stream-imports
+
+//#other-imports
+import akka.{ NotUsed, Done }
+import akka.actor.ActorSystem
+import akka.util.ByteString
+import scala.concurrent._
+import scala.concurrent.duration._
+import java.nio.file.Paths
+//#other-imports
+
+import org.scalatest._
+import org.scalatest.concurrent._
+
+//#main-app
+object Main extends App {
+  // Code here
+}
+//#main-app
+
+class QuickStartDocSpec extends WordSpec with BeforeAndAfterAll with ScalaFutures {
+  implicit val patience = PatienceConfig(5.seconds)
+
+  def println(any: Any) = () // silence printing stuff
+
+  "demonstrate Source" in {
+    //#create-materializer
+    implicit val system = ActorSystem("QuickStart")
+    implicit val materializer = ActorMaterializer()
+    //#create-materializer
+
+    //#create-source
+    val source: Source[Int, NotUsed] = Source(1 to 100)
+    //#create-source
+
+    //#run-source
+    source.runForeach(i => println(i))(materializer)
+    //#run-source
+
+    //#transform-source
+    val factorials = source.scan(BigInt(1))((acc, next) => acc * next)
+
+    val result: Future[IOResult] =
+      factorials
+        .map(num => ByteString(s"$num\n"))
+        .runWith(FileIO.toPath(Paths.get("factorials.txt")))
+    //#transform-source
+
+    //#use-transformed-sink
+    factorials.map(_.toString).runWith(lineSink("factorial2.txt"))
+    //#use-transformed-sink
+
+    //#add-streams
+    factorials
+      .zipWith(Source(0 to 100))((num, idx) => s"$idx! = $num")
+      .throttle(1, 1.second, 1, ThrottleMode.shaping)
+      //#add-streams
+      .take(3)
+      //#add-streams
+      .runForeach(println)
+    //#add-streams
+
+    //#run-source-and-terminate
+    val done: Future[Done] = source.runForeach(i => println(i))(materializer)
+
+    implicit val ec = system.dispatcher
+    done.onComplete(_ => system.terminate())
+    //#run-source-and-terminate
+
+    done.futureValue
+  }
+
+  //#transform-sink
+  def lineSink(filename: String): Sink[String, Future[IOResult]] =
+    Flow[String]
+      .map(s => ByteString(s + "\n"))
+      .toMat(FileIO.toPath(Paths.get(filename)))(Keep.right)
+  //#transform-sink
+
+}