Changes in version 0.3.0:

Bugs fixed:
- config command could invalidate config file on local backend

New features:
- backup: Added escaping of filenames to be compatible with restic
- backup: Don't use temporary files, but save incomplete pack files in-memory
- Allow to limit pack sizes
- rest/rclone backend: Retry operations if they failing
- restore: Use existing files to speed up restore (also makes restore resumable)
- restore: Added --delete option to delete existing files not in snapshot
- restore/prune: Added warm-up possibilities for hot/cold repo
- prune: Remove unneeded packs from cache
- prune: Added repacking of packs which are too small or too large
- self-update: New command to update rustic
- Added syntax SNAPSHOT[:PATH] for many command to access sub-trees within snapshots
- Added support for environmental variables
- Improved help texts
- CI: Added beta builds
- CI: Added dependabot to get automatic PRs for dependency updates
