Re-add suspend resume example

Signed-off-by: Jon Ludlam <jonathan.ludlam@citrix.com>
Move the suspend/resume example into the xen subdir

Signed-off-by: Jon Ludlam <jonathan.ludlam@citrix.com>
Merge branch 'suspend2' of git://github.com/jonludlam/mirage-skeleton
Do not make build depend on configure

via @mor1