ENH: improve file reader support for runTimePostProcessing (#1091)

- support .vtp format for geometry, surface, line, cloud.

- use native reader for handling vtk, vtp, obj, stl surface files.
  For other formats, use the MeshedSurface (the surfMesh lib) to
  handle reading and Foam::vtk::Tools::Patch to handle the
  conversion to vtkPolyData. This combination is more memory efficient.

- update tutorial case to include vtp surface geometry

src/functionObjects/graphics/runTimePostProcessing/functionObjectLine.H

@@ -3,7 +3,7 @@
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
     \\  /    A nd           | Copyright (C) 2015 OpenFOAM Foundation
-     \\/     M anipulation  | Copyright (C) 2016 OpenCFD Ltd.
+     \\/     M anipulation  | Copyright (C) 2016-2018 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -56,9 +56,15 @@ class functionObjectLine
     public pathline,
     public functionObjectBase
 {
-private:
+protected:
 
-    // Private Member Functions
+    // Protected Data
+
+        //- Actor
+        vtkSmartPointer<vtkActor> actor_;
+
+
+    // Protected Member Functions
 
         //- No copy construct
         functionObjectLine(const functionObjectLine&) = delete;
@@ -67,14 +73,6 @@ private:
         void operator=(const functionObjectLine&) = delete;
 
 
-protected:
-
-    // Protected data
-
-        //- Actor
-        vtkSmartPointer<vtkActor> actor_;
-
-
 public:
 
     //- Run-time type information
@@ -88,7 +86,7 @@ public:
         (
             const runTimePostProcessing& parent,
             const dictionary& dict,
-            const HashPtrTable<Function1<vector>, word>& colours
+            const HashPtrTable<Function1<vector>>& colours
         );