(dev/core#183) Change temp table naming for exports

(dev/core#183) Change temp table naming for exports

Testing notes - This is a pretty formulaic change.  The main concern is some kind of typo or bad table name causing a
hard-fail.  To control that risk, we just run the code in a facile way:

* Perform a contact search
* Pick some contacts
* Export them
* Run the export

We do this procedure under a few circumstances:

* With the original code
* With a purposefully bad edit (provoking an expected error)
* With the new code