Error in setup-storage in FAI 4.1

[Thomas Neumann]

> We (Kerim and I) are currently working on getting liblinux-lvm-perl
> patched upstream. If this does not work, we will prepare a new Debian
> version of this library.

I strongly recommend to drop Linux::LVM completely, because the required
functionality is very easily reimplemented:

e.g.:
https://github.com/ThomasNeumann/setup-storage/blob/setup-storage_tn/lib/SetupStorage/LVM.pm
(line 88-140)

Pro Linux::LVM:
 - encapsulates vgdisplay parsing

Contra Linux::LVM:
 - setup-storage uses perhaps 10% of provided functionality
 - bugs must be fixed 'upstream' and existing code/release quality is
pretty bad (IMHO 0.17 being unable to parse vgdisplay due to a misnamed
label is a pretty serious issue - this should not happen)
 - command execution may fail, but library does not notice it

not exactly a bug/problem, but it irks me:
 - command execution leaks StdErr to console