BUG: Use itk::SimpleFilterWatcher instead of itk::FilterWatcher.

Use itk::SimpleFilterWatcher instead of itk::FilterWatcher.

The itk::FilterWatcher class was removed in favour of
itk::SimpleFilterWatcher (and thus, its header file named
itkFilterWatcher.h was deleted) in this gerrit topic:
http://review.source.kitware.com/#/c/23415/

This bug was identified thanks to the following gerrit topic:
http://review.source.kitware.com/#/c/23428/

Author: Jon Haitz Legarreta Gorroño

test/itkFirstOrderTextureFeaturesImageFilterGTest.cxx

@@ -18,7 +18,7 @@
 #include "itkFirstOrderTextureFeaturesImageFilter.h"
 #include "itkFlatStructuringElement.h"
 #include "itkAdditiveGaussianNoiseImageFilter.h"
-#include "itkFilterWatcher.h"
+#include "itkSimpleFilterWatcher.h"
 
 #include "gtest/gtest.h"
 
@@ -77,7 +77,7 @@ TEST(TextureFeatures, FirstOrder_Test1)
   filter->SetKernel( kernel );
   filter->SetInput( noiseFilter->GetOutput() );
 
-  FilterWatcher watcher(filter, "filter");
+  itk::SimpleFilterWatcher watcher(filter, "filter");
 
 
   ImageType::SizeType requestSize = {{10,10}};
@@ -147,7 +147,7 @@ TEST(TextureFeatures, FirstOrder_Test2)
   filter->SetKernel( kernel );
   filter->SetInput( noiseFilter->GetOutput() );
 
-  FilterWatcher watcher(filter, "filter");
+  itk::SimpleFilterWatcher watcher(filter, "filter");
 
 
   ImageType::SizeType requestSize = {{10,10}};