impl de trait for deserial ansi value and rgb

[zwpaper]

deserial json like:

{
    "color_example": "white",
    "ansi_value_example": 255,
     "rgb_example": [255, 255, 255]
}

[zwpaper]

Hi @TimonPost , crossterm color use the default deserial implementation, it can not deserial AnsiValue and Rgb, so that I try to implement the deserialization trait to make it support this format:

{
    "color_example": "white",
    "ansi_value_example": 255,
     "rgb_example": [255, 255, 255]
}

could you please review this when free

[TimonPost]

Thanks for the contribution. It would make sense to merge this into crossterm. Just to be sure I understand it right, this works for all kinds of serde crates?

There is some duplicated test.

[zwpaper]

Hi @TimonPost, yes, it should work for all kinds of serde crates, or it would be a bug.

besides the serde_json in tests, I would use serde_yaml in another project, It could be a validation for that.

[TimonPost]

Thanks for the contribution! Its good like this