cancel queue request on signal to prevent streams from blocking

[oqq]

The amqp extension + library has its own mechanism to remove blocking for requests, if the signal handler is activated.

But the cancelation for requests was not called from this library, so i have moved some code around to get rid of that issue: closes #45

I am not sure about side effects, so please have an extra review round. ;)

[coveralls]

Coverage remained the same at 92.686% when pulling 0e1b18f0e8ae27aeb587f64b1653b9d39ef29217 on oqq:features/interupt_running_consumers into e1f298debdfdf609c742258ccfee37c149dde57c on prolic:master.

[prolic]

@oqq see https://github.com/oqq/HumusAmqp/blob/0e1b18f0e8ae27aeb587f64b1653b9d39ef29217/src/AbstractConsumer.php#L182

this line is 100% blocking, so the shutdown method is never called, unless the block has been removed (f.e. by timeout or message came in)

[oqq]

This is not true for the php-amqplib package. See this File: https://github.com/php-amqplib/php-amqplib/blob/master/PhpAmqpLib/Wire/IO/StreamIO.php and search for canDispatchPcntlSignal.

How I said, this package handles this behavior already like a charm by endless looping requests without blocking. My provided patch works exactly how it should without any script wrapper. Please test it by your own.

[prolic]

manually merged into master