Add recursive 'ignore'

[thorstenspille]

abgleich should support 2 different types of excludes/ignores to be able to build one configuration for a complete zpool with multiple hierachical levels of subvols and datasets.

• exclude a single dataset, but include all subsets (seems to bee the current feature)
• exclude recursively, docker manages it's volumes itself, creates and snapshots many datasets for the container image layers and I don't want to snapshot or backup them. This could be a second config option or support for wildcards (e.g. var/lib/docker*).

The subcommands tree and compare should only list the included datasets and subvols. For displaying the full data there should be an additional parameter (e.g. --full or --show-excludes)

[s-m-e]

Recursive ignores make a hell of a lot of sense, yes.