MediaWiki metadata does not always contain rights

[GreenReaper]

wiki.py assumes that the 'rights' attribute exists in the general siteinfo. It seems that it was previously blank if not set, however this is no longer the case, at least as of 1.23 and perhaps earlier.

        if options.license:
            license_file = options.license
        else:
            rights = general_siteinfo['rights']
            if rights in known_licenses:
                license_file = known_licenses[rights]
            else:
                license_file = None
                self.metadata['license'] = rights

aardc fails with "KeyError: 'rights'" on the general_siteinfo line.

One workaround is to add "--license path/to/text/file" before the "wiki" on the command line.

[itkach]

c86cb5e updates aard-siteinfo to request rightsinfo to be included in siteinfo and 9b1b340, 9b1b340 update wiki.py to look for rightsinfo. That should fix it.