adding videojs

Pulled this out of the new video megabranch so we can properly review that pull request later

Added
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common/app/assets/javascripts/components/videojs
common/app/assets/javascripts/components/videojs-contrib-ads
common/app/assets/javascripts/components/videojs-vast
common/app/assets/javascripts/components/vast-client-js

Modified
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ommon/app/assets/javascripts/bower.json