Dar-backup

2 new features:
- incremental backups against DIFFs
- generate file list of files to be backed up

A few more test cases.

SHA256:
31d93ad594f1485f3e00cd9aa2eafca4feb1df57c501e5278e051fb1314a9c5b dar-backup-linux-v1.0.2.tar.gz

This release is a patch with no new functionality.

- improve return value handling from functions.
- the demo backup definition supplied, backs up the deployed dar-backup directory
- various doc changes

SHA256 digest:
a18a7c3aa4a31e9eeee66a26fec6e2764b03d5790aa72ed085ef4cd980c916d5 dar-backup-linux-v1.0.1.tar.gz

Only files needed to run the script are included in the tar file.

SHA256 digest
ca4658f0109f569ad1b70094b57a53a9fc5d9d830f3ef9d459593f164fe3331a dar-backup-linux-1.0.tar.gz