Initial commit of a XenServer builder script

You execute this script in the Rackspace cloud, it will convert the
instance to a XenServer. A minimal precise VM will be accessible through
the public IP. The XenServer will be accessible through an internal
virtual "mgt" network.

Staging VM username:
    user
XenServer's password:
    password
XenServer's IP address:
    192.168.32.2

Flavor:
    performance1-8
Image:
    Ubuntu 13.04 (Raring Ringtail) (PVHVM beta)

Change-Id: Ibe94e56f6f3ac890e7f269042bc1db525b413efe
Disable reboot and grub update
Escape backslashes
Reboot automatically and skip xva copy

I experienced a bad kernel panic, maybe not copying the xva will help
Download Staging VM through XenServer
Fix - do not escape macaddress
Remove dnsmasq and shorewall config

Change-Id: I0b1905a861dfa6686f5a458c5d0f0c2136a0a026