Lotman should dynamically adjust lots whenever cache rediscovers namespaces

[jhiemstrawisc]

Caches must periodically poll the Director to get namespace information, which caches use to keep a tidy auth/scitokens config. However, as namespaces come and go, Lotman should also be adjusting lots to make sure we don't wind up with unusable lot partitions.

Getting this right will be tricky, because lotman is fed usage updates as diffs by XRootD. This means that the disappearance of a namespace would currently require re-allocation of its lot's disk usage to another lot -- most likely the default lot, but that's not a guarantee. Otherwise, the incoming diffs wouldn't correctly adjust the values Lotman stores.

In addition to usage re-allocation, we should also handle adjustment of lot management policy attributes. Keep the cache full, keep the cache happy!