Merge pull request #823 in SHRINE/shrine from bugfix/SHRINE-3693-remove-cancelled-tasks-from-the to develop
* commit '8fdc28ac5cd00483fa02ef2c5ec5265e3b693733':
Just hold onto the queue and message id to save a lot of memory for SHRINE-3693
Now cancelling the outstanding tasks for SHRINE-3693
Revert "Separated out the scheduler part of LocalMessageQueueMiddleware for SHRINE-3693"
Separated out the scheduler part of LocalMessageQueueMiddleware for SHRINE-3693
