Add script for Ubuntu 14.04 LTS (Trusty)

- Required frustrating testing with the Ubuntu installer, which supports
  a limited subset of kickstart features
- Tested on XenServer Creedence Alpha 4 with Trusty
- Does NOT include XenServer Tools because that requires `xs-tools.iso`
- Ubuntu's installer demands a swap partition or will interrupt, unlike
  Anaconda which smartly spits a warning message but proceeds despite
  not having a swap