Mode 1972 Updated the copy & clone operations so that it's possible to copy & clone an entire workspace into another workspace

Also, copying or cloning a subgraph from a workspace into the root of another workspace is not allowed, because that would mean that the root node would have "behave" as a standard node, at the end of the operation.

When copying/cloning and entire workspace into another workspace, the root node(s) and the `jcr:system` nodes have to be explicitly excluded from the operation.