[ucd/bidi] Implement Bidi_Mirrored UCD property

[behnam]

• [gen] Add bidi_mirrored.rsv generation.

• Add BidiMirrored type to unic-ucd-bidi component, as BinaryCharProperty.

• Add is_bidi_mirrored(char) helper for common use-cases where only the boolean value is needed. This is a pattern we can apply to all Binary properties, like is_alphabetic(char) and is_white_space(char).

• Add CharBidiMirrored and StrBidiMirrored traits to provide easy access to property via char and str types.

Tracker: https://github.com/behnam/rust-unic/issues/134

[behnam]

Thanks, @CAD97, for catching those! Yes, contains() works smoothly.

bors: r+

[bors[bot]]

Build succeeded

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