NettyAsyncHttpProvider not following redirect to lower-cased path

[kamatsuoka]

In NettyAsyncHttpProvider.java, when handling an HTTP redirect, it checks whether the new url is the same as the old url, ignoring case.

It turns out that there are some web servers out there that redirect any mixed-case filenames to the lowercased equivalent.

curl -v http://www.pix-art.de/sykhjN6md5ysGCqDIbm6lt35suI.html
> GET /sykhjN6md5ysGCqDIbm6lt35suI.html HTTP/1.1
> Host: www.pix-art.de
>
< HTTP/1.1 301 Moved Permanently
< Location: http://www.pix-art.de/sykhjn6md5ysgcqdibm6lt35sui.html
< Server: Microsoft-IIS/7.5
< X-Powered-By: ASP.NET

So if you try to get the mixed-case filename, NettyAsyncHttpProvider won't follow the redirect.

[slandelle]

Needs to be backported on 1.7.x