Make close/finish ordering deterministic

Ironically, there was a race condition in this module, because if a
`close` event fired on the original (tmp file) stream while the rename
was in process, then it could result in emitting a `close` event in
advance of the `finish` event, and in advance of the file being in its
proper permanent home.

So, an `openSync` called at that exact time would fail, violating the
expectation that `close` means "I am done with my things and it is safe
to proceed."
v1.0.1