Comment 0 for bug 333936

In <https://pastebin.canonical.com/14180/> we can see that the sourceforgeproject setting is actually a URL. In the last case it is non-ASCII and causes the script to abort. The script should reject unusable settings. Optionally, if the setting can be parsed as a URL, the last path component could be used as the SF project name -- this seems to be a common pattern.