`source_urls = [('http://sourceforge.net/projects/bio-bwa/files/', 'download')]` results in a download URL like `http://sourceforge.net/projects/bio-bwa/files/bwa-1.2.3.tar.gz/download` .

But the URL @JensTimmerman mentioned above (source: http://fedoraproject.org/wiki/Packaging:SourceURL#Sourceforge.net) is better, we should use that (or @stdweird's template, even better).