No functional changes are applied by this patch. Itcleans up string creation, and uses the xe minimal feature to improve readability
Modified the cl-dtg-make-vm script so that we now build two disks for each VM.
The intended use for the disks is that one stores the OS, and the other stores
/local/data. This lets us swap the OS, whilst keeping the data.

I had to do some hackery, because of nastyness in xe. xe vm-install creates
a vdi of 8GB, and attaches it to the guest. The size cannot be specified.
You cannot shrink the size of a vdi. Therefore, I have to delete it
straight after creation.
Merge branch 'upstream'
Release v0.0.3 which builds VMs with two disks
Merge branch 'packaging'