a shell object that can chdir, setenv, and exec commands.
(note that this executes stuff after fork, so permanent changes are cheap
and okay)
Also create it from "host" objects, which simplifies parameter passing.
- clean up clock handling, jobs with timer.
- pass more parameters thru state
- tweak the engine to handle distfiles
- lots of new code in Fetch for new jobs.
Deprecate: -t and -T
use -DCONNECTION_TIMEOUT=... -DDISPLAY_TIMEOUT=... instead
New feature: -DSTUCK_TIMEOUT=
kill tasks when they don't show any progress for that long.
- if several cores are available, recheck errors, so that we're not stuck
waiting for a core to finish to start new shit.
- $logdir/stop-<machine_name> allows you to stop a given machine while
you clean it up and (possibly) restart it (e.g., won't start new jobs)