Don't block on the data handle lock while holding the schema lock.  If we can't get the data handle lock immediately, give up attempting to close the file: the sweep server will retry.
Wait for the oldest transaction ID to catch up to current during connection close.  This avoids an EBUSY if we try to close when the eviction server is in the middle of a long-running operation such as evicting a 100MB page from an LSM tree.

refs #1201