Request-Limit amount of rescans running at the same time.

Can you add a queue system for re-scans that limits the amount that are concurrently running. It would be great if the limit was user configurable.

Or maybe an user configurable additive offset for the re-scan time. As an example: #1 on streams list re-scans every [configured re-scan time + offset] #2 [configured re-scan time + 2*offset] and so on.
