Document textTransform support

[macintoshhelper]

Proposal/Feature-request:

Might be worth supporting the textTransform CSS property. This is supported by React Native now: https://reactnative.dev/docs/text-style-props#texttransform

capitalize isn't supported by Sketch though, so maybe this should be a transformation applied to the text string children manually? Or added to the docs with a strikethrough for capitalize.

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Sorry, forgot to check existing issues 😄, just checked the source and it already exists.

textTransform is missing from the docs though, so will add it soon, makes sense to do it together with cleaning up the docs a bit more though so the PR isn't too atomic.