Revert "update thinkphp"

This reverts commit 4df9baabeecc591a3e82bfa6bf813ffab8054cb9, reversing
changes made to ff955e4012aa712ebdf9d7b6db0e74f8595d8e06.

	modified:   ThinkPHP/Common/functions.php
	modified:   ThinkPHP/Library/Think/Db/Driver/Mysql.class.php
	modified:   ThinkPHP/Library/Think/Db/Driver/Mysqli.class.php