cc1: warnings being treated as errors
libxl/libxl_driver.c: In function 'libxlDomainSetVcpusFlags':
libxl/libxl_driver.c:1570:14: error: cast from function call of type 'double' to non-matching type 'unsigned int' [-Wbad-function-cast]
libxl/libxl_driver.c:1578:15: error: cast from function call of type 'double' to non-matching type 'unsigned int' [-Wbad-function-cast]

This was the only use of floor() and ceil(), and floating-point
is overkill for power-of-two manipulations.

* src/libxl/libxl_driver.c (libxlDomainSetVcpusFlags): Avoid -lm
for trivial computations.

The domainSetAutostart function is nearly identical to the one from qemu.

  When you happen to have a libvirtd binary compiled with the
libxenlight driver (say you have installed xen-4.1 libraries)
but not running a xen enabled system, then libvirtd fails to start.

The cause is that libxlStartup() returns -1 when failing to initialize
the library, and this propagates to virStateInitialize() which consider
this a failure. We should only exit libxlStartup with an error code
if something like an allocation error occurs, not if the driver failed
to initialize.

* src/libxl/libxl_driver.c: fix libxlStartup() to not return -1
  when failing to initialize the libxenlight library

* src/libxl/libxl_driver.c: implements libxlDomainSuspend and
  libxlDomainResume

* src/libxl/libxl_driver.c: implements libxlDomainGetOSType

* src/libxl/libxl_driver.c: implements libxlDomainGetSchedulerType

* src/Makefile.am src/libvirt_private.syms configure.ac: share and
  reuse the sexpr routines from sexpr.h of the old xen driver
* src/libxl/libxl_driver.c: implements libxlDomainXMLFromNative and
  libxlDomainXMLToNative

Hook the virtual cpu functions to their libxenlight counterparts

* src/libxl/libxl_driver.c: implements libxlDomainSetVcpus,
  libxlDomainGetVcpus, libxlDomainSetVcpusFlags,
  libxlDomainGetVcpusFlags and libxlDomainPinVcpu

* src/libxl/libxl_conf.[ch] src/libxl/libxl_driver.[ch]: add authors
  after the licence template

* src/libxl/libxl_conf.h: add the necessary fields to the driver
  private structure
* src/libxl/libxl_driver.c: add lifecycle event support and entry
  points for event(de)register(any)

* src/libxl/libxl_driver.c: use ignore_value() in libxlDomainObjUnref
  and libxlCreateDomEvents

It is possible to set a migration speed limit when starting
migration. This new API allows the speed limit to be changed
on the fly to adjust to changing conditions

* src/driver.h, src/libvirt.c, src/libvirt_public.syms,
  include/libvirt/libvirt.h.in: Add virDomainMigrateSetMaxSpeed
* src/esx/esx_driver.c, src/lxc/lxc_driver.c,
  src/opennebula/one_driver.c, src/openvz/openvz_driver.c,
  src/phyp/phyp_driver.c, src/qemu/qemu_driver.c,
  src/remote/remote_driver.c, src/test/test_driver.c,
  src/uml/uml_driver.c, src/vbox/vbox_tmpl.c,
  src/vmware/vmware_driver.c, src/xen/xen_driver.c,
  src/libxl/libxl_driver.c: Stub new API

Add a new xen driver based on libxenlight [1], which is the primary
toolstack starting with Xen 4.1.0.  The driver is stateful and runs
privileged only.

Like the existing xen-unified driver, the libxenlight driver is
accessed with xen:// URI.  Driver selection is based on the status
of xend.  If xend is running, the libxenlight driver will not load
and xen:// connections are handled by xen-unified.  If xend is not
running *and* the libxenlight driver is available, xen://
connections are deferred to the libxenlight driver.

V6:
 - Address several code style issues noted by Daniel Veillard
 - Make drive work with xen:/// URI
 - Hold domain object reference while domain is injected in
   libvirt event loop.  Race found and fixed by Markus Groß.

V5:
 - Ensure events are unregistered when domain private data
   is destroyed.  Discovered and fixed by Markus Groß.

V4:
 - Handle restart of libvirtd, reconnecting to previously
   started domains
 - Rebased to current master
 - Tested against Xen 4.1 RC7-pre (c/s 22961:c5d121fd35c0)

V3:
  - Reserve vnc port within driver when autoport=yes

V2:
  - Update to Xen 4.1 RC6-pre (c/s 22940:5a4710640f81)
  - Rebased to current master
  - Plug memory leaks found by Stefano Stabellini and valgrind
  - Handle SHUTDOWN_crash domain death event

[1] http://lists.xensource.com/archives/html/xen-devel/2009-11/msg00436.html