Initial KVM Validation integration

Bring the A15 Fast Model, KVM, and QEMU into the validation lab so you can start a emulated host and then launch a guest inside it.

Use LAVA to orchestrate:
 * A Fast Model Cortex-A15 host running on x86
 * A host rootfs
 * A host kernel
 * A QEMU KVM guest
 * A guest rootfs
 * A guest kernel

so that you can boot the host inside the A15 fast model, then launch
the guest inside the host, then do something inside the single guest.

This is early days so there's a few warts - there's no host or guest
hwpack and, currently, KVM doesn't support Thumb2 guests. Use pre-built kernels to work around the former and a Debian based,
linaro-media-create compatible rootfs for the latter.

This shows that the infrastructure works, lets us do basic CI on QEMU,
and gives us parts that can be replaced as the real versions become
available.

This blueprint has been superseded by http://cards.linaro.org/browse/CARD-233