Compilation fixes for Windows

A bunch of tweaks:

• proper VLA instanciation
• signed/unsigned comparisons
• M_1_PI difficult to get on Windows...

include/otbSARDEMGridImageFilter.txx

@@ -377,9 +377,9 @@ namespace otb
     unsigned int nbLine = static_cast<unsigned int>(outputRegionForThreadSize[1]); 
     unsigned int firstLine = static_cast<unsigned int>(outputRegionForThread.GetIndex()[1]+this->GetOutput()->GetOrigin()[1]);
 
-    double outRange[nbCol*nbLine];
-    double outAzi[nbCol*nbLine];
-    int outNbContribution[nbCol*nbLine];
+    double *outRange = new double[nbCol*nbLine];
+    double *outAzi = new double[nbCol*nbLine];
+    int *outNbContribution = new int[nbCol*nbLine];
 
     // Initialize arrays
     memset(outRange, 0., nbCol*nbLine*sizeof(double));
@@ -476,7 +476,9 @@ namespace otb
 	OutIt.NextLine();
 	++counterLine;
       }
-   
+   delete [] outRange;
+   delete [] outAzi;
+   delete [] outNbContribution;
   }
 
 } /*namespace otb*/