Changelog (v1.38.0...v1.38.1)
- bug #619 Isolate PHP 7 mb_* declarations into bootstrap72.php (@nicolas-grekas)
- bug #617 Polyfill more cURL constants (@GPHemsley)
- bug #618 fix: Correctly define MySQL constants (@mitelg)
- bug #616 Fix grapheme_str_split() on PCRE 8 (@GPHemsley)