Derecho doesn't set JOB_WALLCLOCK_TIME, and only sets it based on the queue sent to

Sam Rabin saw this issue. The wallclock time is hard coded to 12 hours for Derecho in machines/config_batch.xml. So if you set it for you testlist it ends up getting ignored and it uses 12 hours. We'd like to be able to set it and have that value used on submission to Derecho.