Begin porting cssparser to a simple lexer.
Use `Tokenizer.has_more(n)`
Remove `LexState` enum

Will do lexing without passing an explicit state around by having the
loop iteration output and the predictor be some indicator of where the
end of a token is.
First pass of rewriting lexing library.
css_lex: Complete and refactor.

Most functionality is now in the "lexer.rs" file and a separate
"to_json.rs" file contains a JSON serializer.
Adapt JSON tests from cssparser library.

Not all pass right now.
Re-indent test JSON