+ -h | --help display this help
+
+backup-command:
+ -b | --create-backup <file>
+ create .tar.gz of files specified in sysupgrade.conf
+ then exit. Does not flash an image. If file is '-',
+ i.e. stdout, verbosity is set to 0 (i.e. quiet).
+ -r | --restore-backup <file>
+ restore a .tar.gz created with sysupgrade -b
+ then exit. Does not flash an image. If file is '-',
+ the archive is read from stdin.