Third Party Libs in KAboutData

For Kdenlive we are facing the problem that there is no nice way to credit external libs (like e.g. ffmpeg,…) properly.

I think it would be good to extend KAboutData for something like

KAboutData aboutData(…);
aboutData.addThirdPartyLib(i18n("FFmpeg"), i18n("A description…"), QStringLiteral("https://ffmpeg.org"), KAboutLicense::LGPL_V2);

This can then be used by KAboutDialog to display the information.