imgbase: Fix lvs parser

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
ks: Align default LV names

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imagebase: More configurtion options

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imagebase: Fix first layer creation

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>