Incorrect use of isAlpha in deserialization

[maurges]

This is visible for startsIdentifier. The problem is thet I peek output byte by byte, but startsIdentifier works on chars. That means that for example (говно: "스트링") parses, while (жопа: "스트링") does not - because I try startsIdentifier on first byte instead of the whole character

[maurges]

Oh ok, ron-rs doesn't support unicode identifiers, that's why I did it (I think?). But ron-rs supports escaped identifiers, not documented in grammar of course. I think I do want to support unicode identifiers, but it's not a priority now.