cyclades: Fix typo

Remove trailing comma that caused image info to be stored as tuples.
deploy: Install qemu-kvm from wheezy-backports
cyclades: Change default value of setting

Change the default value of the 'GANETI_USE_HOTPLUG' setting in the
configuration file.
cyclades: Handle IndexError in pool-show cmd

Handle IndexError exception that is raised when the user does not
provide a pool ID.
cyclades: Copy VM metadata only for root volume

When taking a snapshot of a volume, copy the metadata of the VM into
the image properties only when the volume is the root volume of the VM.