This brings down the test run from 108 sec to 15 sec.
There is an occasional port conflict because of the nature
the next port is chosen. So far it seems rare enough to live
with it.
These would manifest in the HTTP output as Javascript nulls instead of
empty lists, so we had unintentionally changed the interface while
porting to the new state store. We added code to each HTTP endpoint to
convert nil slices to empty ones so they JSON-ify properly, and we added
tests to catch this in the future.
Frank Schroeder