Description:
------------
Trying to use AMQP_NOACK on AMQPQueue::consume($callback, [int $flags]) complains 
about undefined constants.

pecl/amqp is already installed and is the same as the released version 1.0.7

Using protocol version => 0-9-1

Meanwhile I found out - by using get_declared_constants() - that the current name 
for this constant should be AMQP_AUTOACK, which actually makes more sense and 
matches the amqp ini var: amqp.auto_ack => 0 => 0




Test script:
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$exchangeName = 'DirectExchange';
$queueName = 'Process';
$routingKey = 'This';

// connect
$connection = new AMQPConnection();
$channel = new AMQPChannel($connection);

// configure and declare an exchange
$exchange = new \AMQPExchange($channel);
$exchange->setType(AMQP_EX_TYPE_DIRECT);
$exchange->setName($exchangeName);
$exchange->setFlags(AMQP_DURABLE);
$exchange->declare();

// configure and declare a queue
$queue = new \AMQPQueue($channel);
$queue->setName($queueName);
$queue->setFlags(AMQP_DURABLE);
$queue->declare();

$queue->consume($callback, AMQP_AUTOACK)

Expected result:
----------------
Consume is executed and registered callback is triggered

Actual result:
--------------
PHP Notice:  Use of undefined constant AMQP_NOACK - assumed 'AMQP_NOACK'