Needed by pve2-api-doc

argument parser should be more or less compatible with what
we had in 1.X

We want to share code and use new PVE 2 framework features. So it is no longer possible to distribute this a separate packages.

We currently need 'vzctl exec' for net stats which is clumsy.
And the blkio stats for container does not seem to deliver
correct values.

We now have fully functional openvz vnc console.