set cache=none if option is not defined

Signed-off-by: Alexandre Derumier <aderumier@odiso.com>
bump version to 2.3-13
forbid online resize a virtio windows bootdisk

Currently is give us bsod, it's a windows virtio-blk driver bug.

Signed-off-by: Alexandre Derumier <aderumier@odiso.com>
migration : display qm resume error in task log

Signed-off-by: Alexandre Derumier <aderumier@odiso.com>