qemu: Drop vnc and gdbserver option

They uses a fixed port which prevents multiple instance from running

Signed-off-by: Asias He <asias@cloudius-systems.com>
qemu: Allow multiple instances running at the same time

Create a new qcow image with the backing file pointing the original
image. This way, we will not change the original 'golden image' pulled
from remote repo.

Signed-off-by: Asias He <asias@cloudius-systems.com>
Merge pull request #40 from asias/cow

qemu: Allow multiple instances running at the same time
Revert "qemu: Allow multiple instances running at the same time"

This reverts commit b76e4eb878f2bfdfffe0096412b8d07e7e9d399a. I pulled
too early and Asias has an improved version waiting to be merged.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
vbox: Store VM files under ~/.capstan/instances/vbox

We will store all the files related to an instance under
~/.capstan/instances/vbox/$instance_id for vbox.
qemu: Allow multiple instances running at the same time

Create a new qcow image with the backing file pointing the original
image. This way, we will not change the original 'golden image' pulled
from remote repo.

Signed-off-by: Asias He <asias@cloudius-systems.com>