Color32 fromHex(unsigned int v)

[aismann]

Describe your changes

see Ttitle
Im using it sometimes. Maybe usefull for others too.

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[aismann]

/clang-format

[halx99]

Color32::fromHex should also support alpha value.

[halx99]

Thanks, I have other idea about this PR

[halx99]

Finished by 523c5c3