Add WDR Mediathek to sources

I'd like if you could add this source (It's a report about me, and the discovery of a possible Viking shipwreck, the video is only available on the site for 7 days, so I'd like to save it)

http://www1.wdr.de/mediathek/video/sendungen/lokalzeit-bergisches-land/video-solinger-entdeckt-mutmassliches-winkingerschiff-vor-groenland---am-heimischen-computer-100.html