Deal with the incompatible changes in the VirtualBox 4.1 API.

INetworkAdapter has its different AttachTo* method replaced by
a settable attachmentType property.

The maximum number of network adapters is now requestable per
chipset type.

The OpenMedium method got a bool parameter to request opening
a medium under a new IID.

Add vboxArrayGetWithUintArg to handle new signature variations. Also
refactor vboxArrayGet* implementation to use a common helper function.

Deal with the incompatible changes in the VirtualBox 4.0 API. This
includes major changes in virtual machine and storage medium lookup,
in RDP server property handling, in session/lock handling and other
minor areas.

VirtualBox 4.0 also dropped the old event API and replaced it with a
completely new one. This is not fixed yet and will be addressed in
another patch. Therefore, currently the domain events are supported
for VirtualBox 3.x only.

Based on initial work from Jean-Baptiste Rouault.

MSCOM requires stdcall convention.

These files are borrowed from upstream release versions, and should
not need further edits in the context of libvirt (instead, a new
upstream vbox release would entail adding a new header file).  We do
not re-generate these files as part of libvirt, nor do we want to lose
our minor edits (such as cppi cleanups).

* src/vbox/vbox_CAPI_v2_2.h: Clarify file origins.
* src/vbox/vbox_CAPI_v3_0.h: Likewise.
* src/vbox/vbox_CAPI_v3_1.h: Likewise.
* src/vbox/vbox_CAPI_v3_2.h: Likewise.  Reindent with cppi.

* global: patch created by running:
for f in $(git ls-files '*.[ch]') ; do
    cppi $f > $f.t && mv $f.t $f
done

This solves the 'nsIEventQueue object is null' error when trying
to connect to a VirtualBox 3.1 hypervisor instance.

Also fixed serial port configuration which was broken due to recent
change in virDomainChrDef where targetType was newly added.

* src/Makefile.am: add new files
* src/vbox/vbox_driver.c: add case for version 3.1
* src/vbox/vbox_tmpl.c: refactor common patterns into macros, support for
  version 3.1, serial port configuration fix
* src/vbox/vbox_CAPI_v3_1.h, src/vbox/vbox_V3_1.c: generated code

* src/vbox/vbox_CAPI_v3_0.h: this includes minor API changes for VBox
  3.0.6 released some days ago.

* src/vbox/vbox_driver.c: remove some old 2.5 switches and plug the
  3.0 driver
* src/vbox/vbox_V3_0.c src/vbox/vbox_CAPI_v3_0.h: the driver for
  VirtualBox 3.0
* src/vbox/vbox_tmpl.c: handle the new driver and add event support
* src/Makefile.am: plug in the new module

* configure.in include/libvirt/virterror.h src/Makefile.am
  src/domain_conf.[ch] src/driver.h src/virterror.c src/vbox/README
  src/vbox/vbox_CAPI_v2_2.h src/vbox/vbox_V2_2.c
  src/vbox/vbox_XPCOMCGlue.[ch] src/vbox/vbox_driver.[ch]
  src/vbox/vbox_tmpl.c: integration of the VirtualBox support
  patches by Pritesh Kothari
Daniel