HG-269 Smart resizing for Ooyala player

https://wikia-inc.atlassian.net/browse/HG-269
This overwrites style of the container div for Ooyala video that comes from the API. Size is calculated from viewport size and video's aspect ratio; recalculated on window resize.
Because it's `ooyala/iva` and we don't want slash in a class name. It's copied from here https://github.com/Wikia/mercury/blob/HG-269/public/scripts/mercury/modules/VideoLoader.ts#L34

I thought about abstracting it but is there really a point? It's just one simple line.