Change testing synchronization mechanism

Use a pooling instead of signals from server

This is better because:

 * We avoid to raise a signal to parent process by default
 * We do not use mutexs and shared memory on a signal handler

Change-Id: Id8cde2a8eb4340650974a2f83ba4ae5279383de2
RabbitMQListener: Do not destroy connection when stop listening

Change-Id: Iad5f8914a57ddb884d81f75402f111de42bc4f5a
RabbitMQ: Create a wrapper class for readed messages

Change-Id: I14c3f04e46897ab919db748e4661d2babd2a2ce9
main: Do not let children processes to delete temporal files

Change-Id: I0cc88adf1f902b2823a6b63d9f826bffe9fcf82a