Add new translator for Bundesgesetzblatt (Federal Law Gazette of Germany...

...)

 * It should be freely available online. Can you access it outside from Germany (see test cases)?
 * I would like to attach the pdf directly to the entry, but it didn't suceed so far (iframe, embedded pdf, ...)
 * The icon seems sometimes not to update. It might just be a dom change and not a real new page load. What was the trick here again?
 * AFAIK the end page is not available.
 * Any other comments?
well, what about switching to a page that's not supposed to display an icon? From the page above, click on "Komplette Ausgabe" on the left. Does the icon disappear? It's just that if it's not working for you, it might not work for other users as well, so we would definitely want to figure out why this is the case. Maybe I'm the odd one out and it's only working on my computer. We can troubleshoot this more after we merge and other people can easily test the translator.