New Boolean and Intersection branch

This is code for a new Boolean, vtkBooleanOperationPolyDataFilter2, and a new Intersection, vtkIntersectionPolyDataFilter2. -vtkIntersectionPolyDataFilter2 is very similar to vtkIntersectionPolyDataFilter with bug fixes and the addition of cell and point data on the intersection lines that helps in vtkBooleanOperationPolyDataFilter2. -vtkBooleanOperationPolyDataFilter2 uses a method where the output Boolean is determined by sub-surfaces separated by the intersection lines rather than a signed distance function. This makes it operate much faster and more robustly for larger intersections. More details on these methods are found in this paper: http://www.sciencedirect.com/science/article/pii/S0965997816300230