|Subject:||Allow setting minimum_time_per_loop in the metadata|
`rrr-client` should have an option for setting minimum_time_per_loop, but it should also be specified in the RECENT metadata (with the larger value being used). That way both the mirror admin and the end-user have a choice in how fast/frequently things are mirrored. Related: Maybe the pause/interval between runs should be randomized slightly to minimize chance of many mirrors trying to mirror exactly at the same time. (Not sure if that's likely anyway, so maybe it's pointless).