Adding -u --url option
    
    Adds an alternative to -b/-n which just scrapes the download links
    from a html page. Primarely intended to support rpmfusion, which
    does not have any xmlrpc interface.  First test runs w rpmfusion
    works.
    
    Refactoring bugz, adding AbstractBug + implementations providing
    a new backend framework for obtaining urls implemented by bugz,
    name_bug (-n) and url_bug (new --url).
    
    Use urllib instead of requests; requests expands compressed links
    in some situations causing problems.
    
    bugfixes, doc update
    
    Too big a patch
    
    Command line options fixes, manpage update, bugfixes
    
    Don't use request.