Description of problem:
If a recipe is Cancelled or Aborted before it ever starts, the finish_time will remain NULL. If that happens, the job will be excluded from beaker-log-delete's regular deletion process because it is filtering based on finish_time.

Version-Release number of selected component (if applicable):
21.1

How reproducible:
we have heaps on beaker-devel

Steps to Reproduce:
1. Create a job with "scratch" retention tag, and then cancel it before it can start the recipe -- finish time should be NULL
2. Wait 30 days *or* if lazy, hack the value of the recipeset.queue_time column in the database to be 30 days in the past
3. Run beaker-log-delete on the server

Actual results:
beaker-log-delete ignores the old cancelled job

Expected results:
Old Cancelled and Aborted jobs should be deleted