- regex_match_ex was kind of duplicated.
- regex_match_all uses now integer flags (header like regex_compiler_ex)
- Removed RegexError tag to allow old natives to use these constants without mismatch tag error.
- Made all error params optional
Purpose is to use the PCRE flags and error num directly.
Harcoding flags letters is really not readable and friendly.
Also this makes error params optionnal.