Fix for #21.  (#23)
Fix for #21.  (#23)

* Fix for #21. `SetID` was being called as soon as the VM was created, but a subsequent error caused the VM creation to be incomplete.

Moved the call to `SetID` after the resource was completely created and added `Partial` calls to record the changes that were in progress.

(cherry picked from commit 9ef6c62)

* This is more correct. If the ID is not set, the reference to it is lost, so `resourceVMDelete` cannot take effect. Further, I went through and modified the `SetPartial` calls to map to the pattern used in `resourceVMUpdate`, making them more compatible.

ringods/terraform-provider-xenserver,ringods/terraform-provider-xenserver,ringods/terraform-provider-xenserver