lint: 'nchunks' (line 185) may not have been initialized
Don't track overflow records when doing bulk loads, there's no possibility
of reuse.  Close #763.
Fix hangs in eviction: we're also "busy" if we have a running transaction or hazard pointers.
Read-only workloads need a cache full check.

refs #754
Have test/format reset its cursor before blocking operations like checkpoint.
In LSM cursors, check if the cache is full, then re-check if the LSM cursor is up-to-date.
Move the cache full check to cursor enter, when there are no cursors positioned.
Fix the previous update: if the LSM cursor isn't up-to-date, skip all the other checks.