*: pre scripts are handled kind of kludgily -- might make more sense for Job objects to go into the ready queue when the PRE script should be submitted
 *: document list of parents, not done parents in Job objects
 *: Jobs have lists of parents, pending parents, etc.
-*: list of all jobs, ready queue
+*: Each job has parents, waiting, and children lists (parents and children lists don't change during run; waiting does)