BinaryCleanupJob Fixes

I ran into a couple of small issues with the BinaryCleanupJob that I fixed via a plugin. This pull request encompasses what I needed to change.

- Now using the correct group when rescheduleJob is called for the BinaryCleanupJob. Prior to this change, it was impossible to reschedule the BinaryCleanupJob via property configuration.
- Changed FileUtils.isFileNewer calls to FileUtils.isFileOlder in the BinaryCleanupJob. Prior to this change, files that were newer than the configured BINARY_CLEANUP_FILE_LIFE_HOURS were deleted instead of files that were older than BINARY_CLEANUP_FILE_LIFE_HOURS.