表达式查询：[NOT] BETWEEN ：同sql的[not] between

ThinkPHP3.2.3的[NOT] BETWEEN ：同sql的[not] between查询表达式：

查询条件支持字符串或者数组，例如：

$map['id']  = array('between','1,8');

和下面的等效：

$map['id']  = array('between',array('1','8'));

查询条件就变成 id BETWEEN 1 AND 8

$map['id']  = array('between','1,8');
$User->where($map)->select();