Combine commit operation into a write operation.
TrimmedCursor must apply prefix to keys.
Removed unnecessary finally statement.
Added CipherCrypto implementation.
Added another cipher provider hook.
When lock timeout is zero, never enqueue, never wait, and never detect deadlocks. A zero timeout is useful for avoiding potential deadlocks, and so it should fail fast as timed-out.
Merge remote-tracking branch 'remotes/origin/master' into stream