IncomingCrashACRAController better code

[jarofgreen]

https://github.com/BrokenOpenApp/BrokenOpenApp-Web-Core/blob/master/src/JMBTechnology/BrokenOpenAppCoreBundle/Controller/IncomingCrashACRAController.php

Checks GET or POST at start:

// Check crash conditions
        if (!$this->getRequest()->get('STACK_TRACE',NULL)) {
            $response = new Response("No STACK_TRACE.");
            $response->setStatusCode(200);
            return $response;
        }

But then later only gets data from POST so it is possible for a crash with no stracktrace to be written!

Routing file only allows GET so it shouldn't happen.

But let's make this rock solid and only check POST