Log Message:
Undo the removal of patch-ae in the previous commit, to avoid the
insecure-temporary-files problem patch-ae was supposed to fix.
Provide a new patch-ae that does something more like the right thing.

(The old one tried to open and write to a directory created with
mkdtemp(), so even if this code doesn't fully work it's still an
improvement.)

XXX: compile-tested only, don't have time to do it properly right now...

PKGREVISION++.