默认使用 mysqli引擎

fix MYSQL_ATTR_USE_BUFFERED_QUERY

修复php返回int为string类型，同时删除不用的mysql_xxx方法

Merge branch 'master' of https://github.com/hetao29/slightphp

Merge branch 'master' of https://github.com/hetao29/slightphp

fix log to file not change line

增加 json 的错误类型和 log 类型

Update SLog.php

change $CONSOLE default value is false.

fix each to foreach on php7.2