Cliconfig

:sparkles: Introduce `Config` classs that is a dataclass containing 2 attributes (no methods): the config dict and the list of processing

:tada: Processings !
This release bring the processings to the config routines (merge, load, save). It is possible to apply any function that modify a configuration after and before merging, after loading and before saving. The processings use the list of processing to apply processings recursively via the routines. To use processing, the tags are usefull (like `{'config.parammytag': value}` ). The processings can then trigger on a any tagged key.

Processing module:
-:sparkles: make_processing functions: helpers to create simple processing
- :sparkles: Built-in processing `ProcessMerge` (associated to tags merge_before/after/add) that allow dynamic config merging just in time.
- :sparkles: Built-in processing `ProcessCopy` (associated to tag copy) that allow copying a parameter just before merging.
- :sparkles: Built-in processing `ProcessTyping` (associated to tag type:<my type>) that enforces the type of a parameter.
- :sparkles: tag routines to facilitate the manipulation of tags
- :memo: :heavy_check_mark: Doc and associated tests

- :sparkles: add `merge_config_file` to merge from path (= `merge_config` that includes
config loading)
- :sparkles: add `clean_pre_flat` to solve conflicting flatten and unflatten parameters
before flattening the config
- :rocket: avoid changing keys order in merge_config
- :memo: improve readmes indications and improve docstring examples
- 🏗️ architectural changes in `cliconfig`

Working `cliconfig` module to make and manipulate configs with yaml files merging and CLI.

- :sparkles: `make_config` to make config merging from default configs, additional configs and parameters in CLI.
- :sparkles: `merge` to merge two configs together. Support nested config, flat configs (with '.' delimiter) and mix of two.
- :sparkles: `save_config` and `load_config` to save and load config.
- :sparkles: `show_config` to visualize config in pretty way.
- :memo: Complete documentation with Read the Docs [here](cliconfig.readthedocs.io)
- :art: 10/10 pylint, ruff (flake8 + extensions) and mypy are happy
- :heavy_check_mark: 100% test coverage and integration test for `show_config`