Migrate virtualmachine from vmware to virtualbox

Migrating xp vm to vbox 4.2.2

 * 1) shutdown vmware
 * 2) (optional) convert the disk image to vbox using VBoxManage clonehd
 * 3) Create a new xp vm in vbox ui, and attache the disk image
 * 4) Change chipset of the created vm to ICH9
 * 5) Start the vm, uninstall vmware tools, and install vbox tool