[Feature Suggestion] Allow using `convertFromSnakeCase` strategy instead of CodingKeys

[Zhiyu Zhu/朱智语]

It's not really a problem, but I think this is a great feature that you might want to implement. See the following link for more details.

https://developer.apple.com/documentation/foundation/jsondecoder.keydecodingstrategy/2949105-convertfromsnakecase

[nixzhu]

@ApolloZhu It’s on my todo list.

[nixzhu]

@ApolloZhu Baby version 0.31.0 has a new option --convert-from-snake-case can helps you.