Remove prefetch_size from qos

Since RabbitMQ does not support prefetch_size anymore (keeps it at 0), we should do the same and make the option entirely optional for people that use ActiveMQ

changed milestone to %2.0.0

added Feature Incompatible Needs Tests labels

assigned to @henrietta

mentioned in commit 571a0f74

created branch 7-remove-prefetch_size-from-qos to address this issue

mentioned in commit 5f8dbf2e

mentioned in merge request !5 (merged)

mentioned in commit 344d577b

mentioned in commit 4ac48845

closed

mentioned in commit b9ce877f