Allow finite amount of temporary disk space to job

[ycombinator]

A user-submitted job's proces should be allowed access to a finite amount of scratch disk space, say 500 MB in /tmp.

To quote @rgbkrk's beard: "I guess this means metering disk space".

[rgbkrk]

I noticed in a blog article about codecube, that he had a strategy for disk allocations.

This also made me stumble upon blockspring.

[rgbkrk]

Upstream docker issues: moby/moby#471, moby/moby#3804