[WIP] Added a new method cloneable? to check if VMs/Templates can be cloned or not

issue #253
https://bugzilla.redhat.com/show_bug.cgi?id=1122712
@AparnaKarve This ```cloneable?``` method should be removed and allowed to inherit from the base vm_or_template.rb.  There are other VmInfra provider types supported in the code, like VmMicrosoft, that are not cloneable at this time.  I would think this method should only return true in the leaf-node classes.

This method should move into the vm_vmware.rb and vm_redhat.rb files.