Default .replay.tmpdir to be an hsym

[jonathonmcmurray]

In tickerlogreplay.q, we default hdbdir to be an hsym: https://github.com/DataIntellectTech/TorQ/blob/master/code/processes/tickerlogreplay.q#L109

We should also do the same for tmpdir (defined here: https://github.com/DataIntellectTech/TorQ/blob/master/code/processes/tickerlogreplay.q#L30)

We need to make sure this happens after any user defined value is set (e.g. via config or command line), similar to what we're doing for hdbdir