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- Added a ClientStorage prefetch method to prefetch oids.
When oids are prefetched, requests are made at once, but the caller
doesn't block waiting for the results. Rather, then the caller
later tries to fetch data for one of the object ids, it's either
delivered right away from the ZEO cache, if the prefetch for the
object id has completed, or the caller blocks until the inflight
prefetch completes. (No new request is made.)
- Fixed: SSL clients of servers with signed certs didn't load default
certs and were unable to connect.