自动加版本号

*\* If a third ? is present it's treated as version string. **
如果每个js第一行以特殊注释来标注自己内容的md5 hash，如 /_md5hash=cc5227f18bed7bf3635116ee02ab32fd_/, nginx-http-concat能不能自动提取这行信息出来，附加到uri第三个问号后面，作为版本号？ 多个文件就以多个文件的md5 hash字符相连作为版本号。

这个特殊注释可以在预处理，压缩文件时附加上去。

Start by locating the module code that handles concatenated JavaScript/CSS requests and the existing third-query version-string behavior. Check how requested file contents are read and whether first-line MD5 comments can be extracted; done means concatenating the hashes from all requested files and appending the result after the third question mark.

Written by the indexing model from the issue text.