Optimize SourceForge mirror

The current SourceForge mirror makes 5 redirects before reaching the final URL.
It will not work with less than 5

    $ mr=https://sourceforge.net/projects/msys2/files/REPOS/MSYS2/x86_64
    $ av=pacman-mirrors-20140201-1-any.pkg.tar.xz
    $ wget --spider --max-redirect 1 $mr/$av
    HTTP request sent, awaiting response... 301 Moved Permanently
    1 redirections exceeded.

A change in mirror can reduce the redirects to 1

    $ mr=http://downloads.sourceforge.net/project/msys2/REPOS/MSYS2/x86_64
    $ av=pacman-mirrors-20140201-1-any.pkg.tar.xz
    $ wget --spider --max-redirect 1 $mr/$av
    HTTP request sent, awaiting response... 200 OK
    Length: 1252 (1.2K) [application/octet-stream]
    Remote file exists.