Get configuration for the current used listing.

def _config(self, args, config):
        """ Get configuration for the current used listing.
        """
        webexports = dict((x.args, x) for x in config.subsections('webexport'))
        webexport = webexports.get(args.webexport)
        if webexport is None:
            if args.webexport == u'default':
                raise NotImplementedError('Default webexport not implemented')  # FIXME
            else:
                raise KolektoRuntimeError('Unknown webexport %r' % args.webexport)
        else:
            return {'columns': list(webexport.subsections('column')),
                    'page_title': webexport.get('page_title'),
                    'page_credits': webexport.get('page_credits')}