Update http links to https and sync www.php.net URLs (#14854)

pdo_mysql: "--" should be followed by a whitespace character

This required changing how YYFILL works, with no apparent regressions

pdo_pgsql: add support for dollar-quotes

RFC: http://wiki.php.net/rfc/pdo_driver_specific_parsers

Implemented PDO Driver specific SQL parsers

RFC: http://wiki.php.net/rfc/pdo_driver_specific_parsers