autoreconf invoked to build desauto

[orlitzky]

I think ./configure is invoked as part of https://github.com/gap-packages/guava/blob/master/Makefile.in#L24 to simplify the build instructions (you can run just make rather than cd src/leon; ./configure; cd ../..; make). But I can't explain the autoreconf? I've been using the supplied ./configure script for a while now without issues (by patching out the autoreconf).