title: Using both publishOn and subscribeOn on a flux results in nothing happening
body: <p>Whenever i use both subscribeOn and publishOn nothing is printed.
     If I use only one it will print.
     If I use subscribeOn(Schedulers.immediate()) or elastic it works.
     Any ideea why that is?</p>
  
  <p>It was my understanding that publishOn affects on what thread it gets published and subscribe on on what thread the subscriber runs. Could you please point me in the right direction?</p>
  
  <pre><code>fun test() {
          val testPublisher = EmitterProcessor.create&lt;String&gt;().connect()
          testPublisher
                  .publishOn(Schedulers.elastic())
                  .map { it -&gt;
                      println("map on ${Thread.currentThread().name}")
                      it
                  }
                  .subscribeOn(Schedulers.parallel())  
                  .subscribe { println("subscribe on ${Thread.currentThread().name}") }
          testPublisher.onNext("a")
          testPublisher.onNext("b")
          testPublisher.onNext("c")
          Thread.sleep(5000)
          println("---")
      }
  </code></pre>