[Libguestfs] [PATCH 0/3] v2v: Miscellaneous refactoring and fixes.

Originally an attempt to fix: https://bugzilla.redhat.com/show_bug.cgi?id=1570407 However this isn't a complete fix. The OVA supplied doesn't even conform to VMware's own "specification" (I use the word loosely). The OVF inside the OVA references the disk.vmdk file, but the OVA doesn't contain that disk.vmdk file, only a snapshot called disk.vmdk.000000000. Therefore to really fix this bug we need some major work in input_ova.ml. Nevertheless these changes make sense on their own. Rich.