Since we're downloading arbitrary executable code from websites and
running it, we should at least have some confidence it's the right
thing we're running.
These modules encapsulate individual pieces of functionality and make
the code far more maintainable. This is a pretty big refactoring but
overall a big win.
This is a tricky package to support, since the tar file is improperly
structured and it is not an autotools package. Refactor slightly and
add IS_TAR_BOMB option for this kind of use case.
