HDX/AV: oneIteration seems to be obsolete

[jteresco]

The oneIteration function is probably no longer relevant. With the "Run Options" speeds, similar efficiency gains to oneIteration's initial purpose are already there. This also likely makes the traceActions variable obsolete.

[jteresco]

An experiment: change the oneIteration call in the run mode case to oneAction, and then the traceActions check below is replaced with only a call to oneAction. Is this still reasonably efficient in the case of run modes?