removed AclfBus/BranchRef concept, replaced by Bus/Branch<T>
removed AcscBus/BranchRef, DistBus/BranchRef, replaced by Bus/BranchRef
completed refactor, consolidated AclfBus/Branch/NetwoorkRef,
AcscBus/Branch/NetworkRef, DistBus/BranchRef, DStabBus/BranchRef to
Bus/BranchRef<T>