Bugfix: use of uninitialized variable

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START: backup - February 7, 2014 18:53:13

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                       Config 'config': LOADED
      Containers /mnt/cloud/ArchiveR3/: NOT FOUND
                         Create? (y/n):
                                Backup: ABORT
                               Cleanup: Traceback (most recent call last):
  File "./backup.py", line 334, in <module>
    backup.main()
  File "./backup.py", line 321, in main
    if self.cleanup():
  File "./backup.py", line 104, in cleanup
    if self.archive_mount:
AttributeError: backup instance has no attribute 'archive_mount'