Portable MD5 Function

Usage: hex_md5 ('String');

Author
Jixun.Moe
Version
0.1.2
Created
2014-03-05
Updated
2014-07-17
License
N/A

Origional source to the script / 原始脚本源码来源: http://pajhome.org.uk/crypt/md5/md5.html

Modified to make this portable / 进行了少许更改使其不会污染全局变量.