TODO list:
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- Set the self.commands and self.extensions on the storage extensions, as some storages do not support all commands
- MODE STREAM (it means several commands at the same time without waiting for responses)
- Check more the patterns of searching (wildmat) -> backend.format_wildcards() -> Work in progress
- Fork the server to the background automatically (using fork()?)
- Make a command line option to make the server actually run on the foreground (-f option?)
- Add a --verbose flag to replace the current __DEBUG__ flag