This can make it easier to see changes when the backups are compared within version control.

Note, this changes to always pretty-print the JSON.  You might prefer that it's a configurable option.

This commit introduces the settings option client_cert. It is now
possible to add a file path to a client certificate in the configuration
file or as an environment variable. The default is None.

* **config file:**

```
{
  "general": {
    ...
    "client_cert": "/home/user/.certs/grafana.pem"
  },
  ...
}
```

* **env variable:** CLIENT_CERT

Signed-off-by: Jürgen Löhel <juergen.loehel@inlyse.com>

* refactored to use positional arguments

* refactoring to use positional statements

* refactored, realized argparse is being used in individual commands...
* added backup Makefile
* removed backup_grafana.sh and restore_grafana.sh
* removed docker_entry.sh
* (Need to update README and CHANGELOG...)
* (Need to add support for --verbose)

2) Fixed import statements - don't use `from x import *`, but import only what is needed.
2) Reformatted the code.