Add proper batching to queue requests to prevent timeouts and other buggy behavior

[mitchdowney]

This has been reported by @agates and others. I did not implement batching properly, resulting in situations where the app will iterate through the full Queue when just adding a single item to it or reordering the queue. As a result the queue gets noticeably buggy when you have just 10+ items in it.

[mitchdowney]

Going to save this feature/fix for v5.