Various adjustments and bug fixes
Various adjustments and bug fixes

Fix: force integers to strs in Popen arguments

Refactored verify_file out of unlink_worker
If a file already exists on S3 and is identical, don't re-upload
Add some delays, etc, to allow things to settle
Put a STOP in the gpg_queue for each process

rtucker/backuppc-archive-s3,rtucker/backuppc-archive-s3