Enable 'receive_wait_time' configuration parameter for IronMqProvider

The IronMqProvider was not using 'receive_wait_time' configuration for
long polling but it's supported since IronMQ 1.5.2
(iron-io/iron_mq_php@5e61539).

Update 'receive_wait_time' default value for bc as users unaware of this
configuration and using IronMQ would now notice a 3 second delay when
polling for messages.

May be 'iron_mq_php' dependency should be updated to >=1.5.2

Author: DC*

src/DependencyInjection/Configuration.php

@@ -171,7 +171,7 @@ private function getQueuesNode()
                                 ->example(1)
                             ->end()
                             ->scalarNode('receive_wait_time')
-                                ->defaultValue(3)
+                                ->defaultValue(0)
                                 ->info('How many seconds to Long Poll when requesting messages - if supported')
                                 ->example(3)
                             ->end()

src/Provider/IronMqProvider.php

@@ -172,7 +172,8 @@ public function receive(array $options = [])
         $messages = $this->ironmq->getMessages(
             $this->getNameWithPrefix(),
             $options['messages_to_receive'],
-            $options['message_timeout']
+            $options['message_timeout'],
+            $options['receive_wait_time']
         );
 
         if (!is_array($messages)) {