Per File Timeout

It would be really useful to have a per-file timeout option. Currently I'm transforming a large number of files, and some individual files are causing my transform to hang (seemingly indefinitely). If I could set a timeout on a per-file basis then I could just continue on and transform all other files.

This could work by killing any process which does not produce any output for a sufficiently long time, then putting whatever jobs it had pending into a new process.