This fixes bug #61 (Parser hangs on some input).
The bug is caused by _reTagName (/^\s*(\/?)\s*([^\s\/]+)/) doing too much backtracking when the input string contains many whitespaces.
tests: skip non-js files in tests/
tests: allow tests to change chunk size
default chunk size of 5 is slow with large inputs
fixed slow parsing caused by too many backtracking
[tokenizer] re-added the carriage return as whitespace
apparently Google's gumbo-parser does behave this way: