Add VoD distributor type

Since basically every type of content is distributed via a VoD platform, either directly from the start or some time later, the distributor type should have an option for that. This was proposed five years ago by Peter_pbn but has not yet been implemented so I'm bringing it up again.

While doing that you could also add LaserDisc and HD DVD as an option. Those formats are of course outdated but there are quite a lot of entries which use a format like "video (LaserDisc)" or "DVD (HD DVD)" and that just looks wrong.