src: Import modules one per line

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
iters: Print time spent sending images to target

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
iters: Print per-stage frozen times at the end

Note, that the total freeze time and the last iter
include img sync time and restore time.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>