COMP: Fix compile error on MSVC+Ninja by explicitly exporting symbols

The error message was:

LINK : fatal error LNK1181: cannot open input file 'D:\a\ITKNornir\ITK-build\lib\itkNornir-5.4.lib'

include/itkIRCommon.h

@@ -31,6 +31,8 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 #ifndef itkIRCommon_h
 #define itkIRCommon_h
 
+#include "NornirExport.h"
+
 // common:
 #include <itkSimpleFilterWatcher.h>
 #include <itkImageFileReader.h>
@@ -150,7 +152,7 @@ mask_so(const mask_t * mask)
 // point in BREAK. This is to be used in those cases when you know
 // exactly when you want to hit the breakpoint.
 //
-extern int
+Nornir_EXPORT int
 BREAK(unsigned int i);
 
 //----------------------------------------------------------------

include/itkIRRefineGrid.h

@@ -34,7 +34,7 @@ namespace itk
  *
  */
 template <typename TInputImage, typename TOutputImage>
-class IRRefineGrid : public ImageToImageFilter<TInputImage, TOutputImage>
+class ITK_TEMPLATE_EXPORT IRRefineGrid : public ImageToImageFilter<TInputImage, TOutputImage>
 {
 public:
   ITK_DISALLOW_COPY_AND_MOVE(IRRefineGrid);

src/itkIRCommon.cxx

@@ -59,7 +59,7 @@ pthread_attr_t gomp_thread_attr;
 //----------------------------------------------------------------
 // BREAK
 //
-int
+Nornir_EXPORT int
 BREAK(unsigned int i)
 {
   printf("\n\n\nBREAK BREAK BREAK BREAK BREAK BREAK BREAK: %i\n\n\n\n", i);
@@ -1596,4 +1596,4 @@ rgb_to_hsv(const xyz_t & RGB)
   }
 
   return HSV;
-}
+}