Implementation isn't perfect yet, viewer/renderer doesn't update yet when
the preference is changed so a sequence needs to be re-opened for the change to
take effect.
Previously we had no disk management whatsoever, so we cleared the cache on
every close just to prevent clogging up tester disk space. Now that we are
implementing disk management, there are better things to do on close regarding
disk cache. However, some users may still wish for the app to delete the cache
on close, so it's provided as an option.
Foundation for a fairly simple but likely essential autorecovery process.
Basically the same as what it was in 0.1.x but with a huge improvement: custom
autorecovery intervals. Ironically there isn't any "saving" to be done
just yet, but when there is, this infrastructure will be ready for it.
itsmattkc