tests/functional: use dog instead of qemu-img in 016

It seems that qemu-img command has a bug of using cluster's nr_copies
instead of vdi's original nr_copies when it creates snapshot. This
patch lets 016 not use qemu-img.

Cc: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Cc: Valerio Pachera <sirio81@gmail.com>
Cc: Alessandro Bolgia <alessandro@extensys.it>
Signed-off-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
dog: forbid creating snapshot of hypervolume

Currently it is not supported.

Cc: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Cc: Valerio Pachera <sirio81@gmail.com>
Cc: Alessandro Bolgia <alessandro@extensys.it>
Signed-off-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
dog: add a new subcommand "dog vdi object dump-inode" for diagnosing inode object

This patch adds a tool for diagnosing inode object.

How to use:
$ dog vdi object dump-inode <path of inode file>

Sample of output:
name: test
tag:
create_time: 5368f57a0a96d0c0
snap_ctime: 0
vm_clock_nsec: 0
copy_policy: 0
store_policy: 0
nr_copies: 3
block_size_shift: 22
snap_id: 1
vdi_id: 7c2b25
parent_vdi_id: 0
btree_counter: 0
data_vdi_id:

Cc: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Cc: Valerio Pachera <sirio81@gmail.com>
Cc: Alessandro Bolgia <alessandro@extensys.it>
Signed-off-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
dog: use nr_copies of inode object instead of command line parameter

Current "dog vdi clone" has a possibility of creating clone volume
which has a different replica number from its original volume when it
receives -c option. This patch forbid such a situation by letting
vdi_clone() use inode->nr_copies instead of vdi_cmd_data.nr_copies
(the variable which holds a value passed with -c option).

Cc: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Cc: Valerio Pachera <sirio81@gmail.com>
Cc: Alessandro Bolgia <alessandro@extensys.it>
Signed-off-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>