feature-h264-videostorage mp4 container

Just to confuse things in the two issues I am swapping feature-h264-videostorage to mp4 as the container option. This should enable more browsers to work with the GUI hacks we have in place. I am loathe to spend too much time on the GUI if @kylejohnson is giving us a new one. Also I am only updating classic skin.

Is this tested in full? No, but putting it out there for people to try and give feedback.