HYC-1988 - Handle soffice pptx

[bbpennel]

https://unclibrary.atlassian.net/browse/HYC-1988

• If an soffice run times out, the job will attempt a graceful termination, followed by a hard kill. It also now reaps the process if it was killed, to prevent defunct processes from sticking around forever
• Added a lock to soffice processing to prevent multiple runs at once, since apparently it does not support this
  • Added explicit dependency on redlock, which was already getting included via hyrax
• Decreased the number of retries per job from 5 to 3, since jobs rarely recover and block up queues for long periods
• Allow soffice path to be configured from a property