br.de extractor can't grab some videos

[ivan]

in #youtube-dl says:

There is already a functional extractor called BR (Bayerischer Rundfunk Mediathek). But the BR-extractor can not download, for example, these videos:

http://www.br.de/nachrichten/schaeuble-haushaltsentwurf-bundestag-100.html

http://www.br.de/radio/bayern1/service/team/videos/team-video-erdelt100.html

http://www.br.de/fernsehen/br-alpha/sendungen/kant-fuer-anfaenger/kritik-der-reinen-vernunft/kant-kritik-01-metaphysik100.html

The sites under www.br.de/nachrichten/, www.br.de/radio/, www.br.de/fernsehen/ with embedded videos use the same kind of XML file for the video information as the sites under www.br.de/mediathek/ do. (Search "dataURL" in the source of the html files to get the link to the XML file.) That is why I am very sure that it is easy to extend the support of the BR-extractor.

cc @soult