[Suggestion] Add video support

[nkoester]

My gallery contains short videos which were mostly recorded by mobile phones and/or cut together from longer ones. I would love to also have these within the library and allow watching them in the fullscreen view.

(This might be feature-creep. If so please close this issue. But there was no issue regarding videos, so I went ahead and suggested it)

[cbenning]

Seems reasonable, as it can probably be done almost entirely on the client side. We've need to detect a video, add a flag to the metadata and then have the React Code actually provide a streaming widget or something?

[nkoester]

That sounds good. Maybe even extract an image to use as a thumbnail.

[satchlj]

I would also love this feature.