The policy file has both a LIST generation rule and a EXTERNAL LIST
consumer rule.  It uses the ESCAPE term to URL encode the ouput
generated by the LIST.
The external target script simply concats LIST files sent to it.
The mmapplypolicy command adds an additonal variable JOBID to
allow that to be passed as an OPT to the external script.
This let's us distinguish the ouput of one job from the next.