Do not retry SF downloads by directly accessing mirrors. This is
necessary because the main SF download server redirects our possibly
outdated paths to the required full path, but mirrors do not do so
(meaning that there is no point in accessing the mirrors directly).
Instead, we now retry the download from the main server several times
(we may be redirected to different mirrors on each try).
I implemented this by reducing the SF mirror list to just the main
server, and adding wget's --retry-connrefused option so that we
continue retrying when an SF mirror is down (as it will also retry for
non-SF servers, I also reduced the number of tries from 5 to 3, to
avoid having too many retries).
git-svn-id: https://svn.aros.org/svn/aros/trunk/AROS@54981 fb15a70f-31f2-0310-bbcc-cdcc74a49acc