Refactor the setting/config management with pedantic

[you-n-g]

🌟 Feature Description

Refactor the setting management with pedantic.

Motivation

Qlib's setting/config management is based on a dict, which is extremely free but hard to read.
We hope to manage it with pedantic, which can support rich docstring and annotation.

[ChiahungTai]

Will this be an issue?

The usage of decorators may affect the performance of your application. For this reason, I would highly recommend you to disable the decorators if your code runs in a productive environment.

[ChiahungTai]

@you-n-g
The dataconf might be another solution.
The config file looks like very flexible .
But it only support the python >= 3.8.

https://towardsdatascience.com/configuration-files-in-python-using-dataclasses-ec8528e72e01
https://github.com/zifeo/dataconf

[ChiahungTai]

dataconf is so amazing. It can referece the type of class by the config value type.....
See the people and zone in Config.

[ChiahungTai]

@you-n-g
Another good introduction for hocon format.
https://www.w3schools.io/file/hocon-introduction/