Switch to new OpenVox packages

[bastelfreak]

also contains #153

[ekohl]

Crazy idea perhaps, but I've been thinking about how we declare Vox support. In metadata.json there's a requirements section that typically something like this today:

  "requirements": [
    {
      "name": "puppet",
      "version_requirement": ">= 7.0.0 < 9.0.0"
    }
  ],

I'd like us to start looking at vox instead of puppet. In the beginning we can keep puppet in there, but eventually drop it to signal we no longer support Perforce's builds.