Add Perdiodic Timer and nextiterationSleepingTime

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Add link to reactPhp

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README.md

@@ -1,6 +1,6 @@
 # DaemonBundle [![Build Status](https://travis-ci.org/M6Web/DaemonBundle.svg?branch=master)](https://travis-ci.org/M6Web/DaemonBundle)
 
-Allows you to create daemonized commands.
+Allows you to create daemonized commands with the [React event-loop component](https://github.com/reactphp/event-loop).
 
 ## Installation
 
@@ -28,7 +28,7 @@ Note: For Symfony versions ">=2.3 && <3.0" support, you can use `"m6web/daemon-b
 
 You can optionally define events which are triggered each X iterations :
 
-```yml
+```yaml
 m6_web_daemon:
     iterations_events:
         -
@@ -41,6 +41,8 @@ m6_web_daemon:
 
 ## Write command
 
+This command use the [event-loop component](https://github.com/reactphp/event-loop#usage) that uses [ReactPHP](https://reactphp.org) for execute loops; and other tasks asynchronously.
+
 ```php
 <?php
 
@@ -64,6 +66,16 @@ class MyDaemonizedCommand extends DaemonCommand
 
         // Add your own optional callback : called every 10 iterations
         $this->addIterationsIntervalCallback(10, [$this, 'executeEveryTenLoops']);
+
+        // You can add your own Periodic Timer,
+        // In this timer  will be called every 0.5s.
+        $daemon = $this;
+        $this->loop->addPeriodicTimer(0.5, function ($timer) use ($daemon) {
+            // It's the last loop, cancel the timer.
+            if ($daemon->isLastLoop()) {
+                $daemon->loop->cancelTimer($timer);
+            }
+        });
     }
 
     /**
@@ -72,8 +84,12 @@ class MyDaemonizedCommand extends DaemonCommand
     protected function execute(InputInterface $input, OutputInterface $output)
     {
         $output->writeln("Iteration");
-
-        usleep(100000);
+
+        // This method helps to give back the CPU to the react-loop (here for 1000 $µseconds).
+        // So you can wait between two iterations if your workers has nothing to do.
+
+        // We do not recommand to use sleep() or usleep() anymore.
+        $this->setNextIterationSleepingTime(1000); // Every milliseconds
     }
 
     /**