fully automate parallel-find.pl (all but getting tokens)

[price]

It'd be great if we could get the whole scripts-version list by just kinit me/root; aklog; parallel-find.pl.

Remaining things to be fixed for that to happen:

• rather than stop if the versions directory exists, remove it and go on ahead; use a separate lock-file

• figure out how to wait for everything to finish; then do the cat inside the script. (If no Right Way presents itself, just fall back on the conservative heuristic in get-versions.pl.)

• the hanging-in-sipb-cell problem of #69