[uievents-code] Rename OSLeft/Right to MetaLeft/Right (#7)

Since we renamed 'OS' to 'Meta' in for the |key| values, it makes sense to do the same for the |code| values.

Making this change would make all the modifier keys consistent between |key|, |code| and the modifier flags.


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Reply to this email directly or view it on GitHub:
https://github.com/w3c/uievents-code/issues/7