**README**
- Overhaul; changed docs to be better aligned to the new `backup.sh`.
- Add example `docker-compose`.
**Dockerfile**
- Install `zip`.
- Remove installation of `sqlite`.
- Remove unnecessary variables.
**backup.sh**
- Overhaul; now zips all required and recommended files and directories stated at [vaultwarden docs](https://github.com/dani-garcia/vaultwarden/wiki/Backing-up-your-vault).
- Removed deleting old backups; will be added later on in a separate script.
**entrypoint.sh**
- Removed creating folders.
