Make ComputeManager _running_deleted_instances query by uuid

Reuse existing _get_instances_on_driver method to query driver for
running instances.

Resolves bug 1129519.

Change-Id: I9186b289fadfc4414874b3ba52195e9acfac18b4
Add ssh port and key based auth to VPD.

This patch adds the ablity to set ssh port, and use key based
authentication for VPD.

This patch adds config options:
    virtual_power_ssh_port: port to ssh to on virtual power host
    virtual_power_host_key: private key file for ssh auth

Note: Key file must be able to be read by user nova is running as.

      This patch switches the default virtual_power_type from 'vbox'
      to 'virsh' to match the most common usage.

Fix Bug 1136010

Change-Id: Id89878d63d26602bb3eacc2a2ce7902d9bd33d61
Authored-by: Chris Krelle <nobodycam@gmail.com>
Merge "Make ComputeManager _running_deleted_instances query by uuid"
Merge "Add ssh port and key based auth to VPD."