Updated mediawiki/extensions
Project: mediawiki/extensions/MultimediaViewer  c173de46ae3233809ce519dac8067d03032c9874

Add explanatory one-liners to share & embed

Change-Id: Id8eb7020296004dae83d63c37393c29142928dd6
Mingle: https://wikimedia.mingle.thoughtworks.com/projects/multimedia/cards/379