virsh: Improve the job type reported of virsh cmd blockcommit

When starting an active block commit job in virsh, it will report
"Block Commit started", but for more precise message it could
report "Active Block Commit started".

Signed-off-by: Shanzhi Yu <shyu@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
vbox: Fix copyright mistake

I made a mistake on copyright in patch 7f0f415b87.

If I copied codes from one file to another, I should copy the
copyright announcement as well. So this patch makes up the
copyright which I should have added in the previous patch.
vbox: Remove VBOX_OBJECT_CHECK macro

We should follow the rules that CHECK macro only do checking works.
But this VBOX_OBJECT_CHECK and VBOX_OBJECT_HOST_CHECK declared some
varibles at the same time, which broke the rule. So the patch
removed this macros and dispatched it in source code.

The storage driver is still not rewriten at this point. So, I
remains the VBOX_OBJECT_CHECK macro in vbox_tmpl.c. But this will
finally be removed in patch 'vbox: Remove unused things in vbox_tmpl.c'
vbox: move common codes to vbox_common.h

There are lots of macro declarations in vbox_common.c,
vbox_network.c, and the coming vbox_storage.c which simply the API
calling. Since they are totally the same. We shouldn't keep three
copies of that, so they are moved to vbox_common.h.

Note: The macros are quite different from those in vbox_tmpl.c,
      because they are using different API.
vbox: Rewrite vbox-independent functions

This patch rewrites the following functions
    *vboxStorageOpen
    *vboxStorageClose
    *vboxConnectNumOfStoragePools
    *vboxConnectListStoragePools
    *vboxStoragePoolLookupByName

These functions do not call any vbox API, so I directly move it
from vbox_tmpl.c to vbox_storage.c

A small improvement is made on vboxConnectListStoragePools.
The if condition nnames == 1 is modified to nnames > 0. So if the
caller put more than one slot to get active storage pools, the new
function will return exactly one, while the old one would only
return 0.
vbox: Rewrite vboxStoragePoolNumOfVolumes

We use typedef IMedium IHardDisk to make IHardDisk hierachy from
IMedium (Actually it did on vbox 2.2 and 3.0's C++ API).
So when calling
    VBOX_MEDIUM_FUNC_ARG*(IHardDisk, func, args)
we can directly replace it to
    gVBoxAPI.UIMedium.func(IHardDisk, args)

When dealing with this two types, we get some rules from it's
hierachy relationship.

When using IHardDisk and IMedium as input, we can't transfer a
IMedium to IHardDisk. Like:
    gVBoxAPI.UIHardDisk.func(IHardDisk *hardDisk, args)
    Here, we can't put a *IMedium as a argument.

When using IHardDisk and IMedium as output, we can't transfer a
IHardDisk to IMedium. Like:
    gVBoxAPI.UIMachine.GetMedium(IMedium **out)
    Here, we can't put a **IHardDisk as a argument. If this case
    do happen, we either change the API to GetHardDisk or write a
    new one.
vbox: Rewrite vboxStoragePoolListVolumes
vbox: Rewrite vboxStorageVolLookupByName
vbox: Rewrite vboxStorageVolLookupByKey
vbox: Make FindMedium support old vbox versions

In old version, function FindMedium in UIVirtualBox doesn't work
for vbox2.2 and 3.0. We assume it will not be used when vbox in
these versions.

But when rewriting vboxStorageVolLookupByPath, we found it was
compatibe to use FindMedium to get a IHardDisk object, even in
vbox old versions. To achieve this, first make FindMedium call
FindHardDisk when VBOX_API_VERSION < 4000000.
Then change the argument type **IMedium to **IHardDisk. (As the
rules in heriachy, we can't transfer a IHardDisk to match
IMedium in output)

In vbox 2.2 and 3.0, the caller must be aware that they will get
a IHardDisk object in return.
vbox: Rewrite vboxStorageVolLookupByPath
vbox: Make CreateHardDisk support all vbox versions

The CreateHardDiskMedium only support create HardDisk for medium
type, and it only works when vbox version >= 3.1. This patch make
the function workable with all vbox versions and rename it as
CreateHardDisk.

In vbox 2.2 and 3.0 this function will create a IHardDisk object.
In vbox later than 3.0, this function will create a IMedium object.
vbox: Rewrite vboxStorageVolCreateXML

If the <path> in target element is not given, libvirt will put the
new volume in ~/.VirtualBox by default.
vbox: Make IMediumAttachment work with vbox2.2 and 3.0

The GetMedium will always return a IHardDisk object them.
In 2.2 and 3.0, it is what GetHardDisk exactly do. In 3.1 and later,
The IMedium is same as IHardDisk.
vbox: Rewrite vboxStorageVolDelete

The API on IHardDiskAttachment is merged into IMediumAttachment.
So, we don't need it anymore.
vbox: Rewrite vboxStorageVolGetInfo
vbox: Rewrite vboxStorageVolGetXMLDesc
vbox: Rewrite vboxStorageVolGetPath
vbox: New storage driver

This patch provides the new stroage driver for vbox. The work
is similar with patch 87dea4fc and the next b4022de33.
vbox: Remove unused things in vbox_tmpl.c

After rewriting the whole driver, Only version specified code is
remained in vbox_tmpl.c. So, this patch removes those unused macros
header files in vbox_tmpl.c.