Usage: redo-log [-c] [-r] target [| tai64nlocal]

Display kept target's stderr with TAI64N timestamped lines. Only the
last build is kept. You must enable stderr keeping with either -k,
or REDO_LOGS=1. -c option show the exact command invoked, start and
finish time. -r option recursively and linearly show also all deeper
redo calls and their [cmd/Logs].
