core: Sync Template disks with new GUID.

Currently ImportVmTemplateCommand use two different kinds of containers
when importing a Template, disks GUIDs and image GUIDs.

Those two containers are correlated, and should be reflected in a map
so it will remain in sync, same as we use in ImportVmCommand.

Signed-off-by: Maor Lipchuk <mlipchuk@redhat.com>
Change-Id: I5d0ef009e24aac07e2623dbef0fb762ca333888c
core: Update managed device map when importing a cloned VM.

When importing a cloned VM or Template, we generate a new guid for each disk.
Those new guids should be correlated with the mangedDeviceMap contained
in the VM/Template, so it will keep all the devices configuration as in the old
VM/Template.

Signed-off-by: Maor Lipchuk <mlipchuk@redhat.com>
Bug-Url: https://bugzilla.redhat.com/976469
Change-Id: I65a99cc0783f670b9288cc9a066cda4d253492a6