File-storehouse

- minor: Fix GitHub actions that prepares this package for release
- minor: Fix broken link at the README file
- minor: Fix some texts around

- minor: Add JSON load/dump transformation
- minor: Add S3 engine
- minor: Add documentation page (in progress)
- minor: Add encode/decode transformation
- minor: Add file managers using Mapping and MutableMapping protocols
- minor: Add numerated file key mapping
- minor: Add numerated folder key mapping
- minor: Add raw key mapping

- minor: Setup repository