bug#36402: installation error

[Mathieu Othacehe]

Hey Ludo,

> Does that make sense?
>
> I think we should audit and adjust Guile-Parted in that spirit.  WDYT?

Sorry for the delay!

I followed your advice and hid all destroy related functions behind
pointer finalizers. I also added some unit tests to Guile-Parted.

I pushed everything but feel free to comment! Then, I'll make a new
release and try to adapt the installer to those changes.

Thanks,

Mathieu