Multiply updates

    * Fix output processing
      for predictable qemu artifact naming
    * install-recommends=false for ubuntu16
    * add zerofree for lvm case
    * Fix PACKER_ARGS pass

Change-Id: I023b73963aeb7c1d562dbc6b1e414363de913d90
diff --git a/common/zerodisk.sh b/common/zerodisk.sh
index 9b20b18..0a0a05f 100644
--- a/common/zerodisk.sh
+++ b/common/zerodisk.sh
@@ -1,4 +1,12 @@
+#!/bin/bash
+set -x
+
 dd if=/dev/zero of=/EMPTY bs=1M || true
 rm -f /EMPTY
+
+for m in $(cat /proc/mounts |grep '/dev/mapper/vg0' | awk '{print $2}'); do
+  dd if=/dev/zero of=${m}/EMPTY bs=1M || true
+  rm -fv ${m}/EMPTY
+done
 echo 3 > /proc/sys/vm/drop_caches
 sync