testscript: import timeout behavior from stdlib
This uses the -test.timeout flag (or the Params.Deadline field) to send first SIGQUIT (to get a stack trace) and then SIGKILL to a stuck command. It's mostly imported from the current stdlib code, with tweaks to work around the lack of Deadline and Cleanup method access.
Did you somehow write this PR on top of an older master? GitHub reports conflicts :)
Ah yep, I did, I've been using this for a bit in my fork. I'll rebase.
Conflict resolved! :)
There are conflicts again, my apologies. We recently merged a regression in the -continue flag, and I forgot that this was in flight already. If you can fix them again, which should hopefully not be too hard, I'll make sure to review quickly.
Done!