partly revert patch 1191. was only committed by accident

[[Imported from SVN: r1194]]

dune/istl/test/matrixtest.cc

@@ -288,7 +288,7 @@ int main()
           matrix[i][j][k][l] = (i+j)/((double)(k*l));            // just anything
 
   testSuperMatrix(matrix);
-#if 0
+
   // ////////////////////////////////////////////////////////////
   //   Test the BCRSMatrix class -- a sparse dynamic matrix
   // ////////////////////////////////////////////////////////////
@@ -397,5 +397,5 @@ int main()
   sIdMatrix = 3.1459;
 
   testMatrix(sIdMatrix, fvX, fvY);
-#endif
+
 }