clone method

Clone method of BordersCollecton.

Implementation

BordersCollection clone() {
  final BordersCollection bordersCollection = BordersCollection(workbook);
  bordersCollection.all = (all as CellBorder).clone();
  bordersCollection.left = (left as CellBorder).clone();
  bordersCollection.right = (right as CellBorder).clone();
  bordersCollection.top = (top as CellBorder).clone();
  bordersCollection.bottom = (bottom as CellBorder).clone();
  return bordersCollection;
}