Use longest arc with reentrant polar angle

Change-Id: I0ddf6c98a28219d849bad77845611bfc83f4f359

Hybrid/Testing/Cxx/TestPolarAxes.cxx

@@ -82,7 +82,7 @@ int TestPolarAxes( int argc, char * argv [] )
   polaxes->SetPole( .5, 1., 3. );
   polaxes->SetAutoScaleRadius( false );
   polaxes->SetMaximumRadius( 3. );
-  polaxes->SetMaximumAngle( 180. );
+  polaxes->SetMaximumAngle( 200. );
   polaxes->SetNumberOfRadialAxes( 7 );
   polaxes->SetCamera( renderer->GetActiveCamera() );
   polaxes->SetRadialLabelFormat( "%6.1f" );

Hybrid/vtkPolarAxesActor.cxx

@@ -770,6 +770,7 @@ void vtkPolarAxesActor::BuildPolarAxisLabelsArcs( double* O,
       arc->SetPoint1( O[0] + val, O[1], O[2] );
       arc->SetPoint2( O[0] + x, O[1] + y, O[2] );
       arc->SetResolution( arcResolution );
+      arc->SetNegative( this->MaximumAngle > 180. );
       arc->Update();
       
       // Append new polar arc to existing ones