VDPAU breaks on certain video clips

[Jonathan Thomas]

Disabled VDPAU on all producers in the XML OpenShot file. This is to prevent issues related to vdpau. Many reports have been submitted to me where vdpau is breaking a video clip, which is why I am disabling it.

VDPAU is not as effective in video editing, as opposed to video playback. It does help lower the CPU, but it only helps a little bit. So, disabling this gives us much greater stability, and a little worse CPU. I think it's a good trade off (for now).