This operation returns a top level topological link given its name.

Operation Exceptions:
1. NOT_IMPLEMENTED - Raised if EMS cannot support this service.
2. INTERNAL_ERROR - Raised in case of non-specific EMS internal failure.
3. INVALID_INPUT - Raised when topoLinkName does not reference a top level topological link object.
4. ENTITY_NOT_FOUND - Raised when topoLinkName references a top level topological link object that
    does not exist.
