Auto-generate test build scripts

This way I don't have to type in a whole bunch of nasty code every
time I try and generate a new test.  I'm starting to get worried that
this "bash script output as Configfile" stuff is going to end up
creeping so many features that I have a million different versions of
every magic script (ie, pconfigure will turn into autoconf), but I
guess that's the price of supporting lots of weird build
infastructures...

I think in this case it's worth the wackiness.