changed baseline value for test image in img io tests to expose more rounding...

changed baseline value for test image in img io tests to expose more rounding errors on old machines

modules/io/tests/test_io_img.cc

@@ -52,7 +52,7 @@ BOOST_AUTO_TEST_CASE(test_io_img)
   for (img::ExtentIterator i(testimage.GetExtent()); !i.AtEnd(); ++i, ++counter) {
    testimage.SetReal(i, counter);
   }
-  testimage+=0.01; //if all values are > 0.0 we can use close_at_tolerance
+  testimage+=5.01; //if all values are > 0.0 we can use close_at_tolerance
   const String fname("temp_img.tmp");
   std::map<String,ImageFormatBase*> float_formats;
   float_formats["DX"]=new DX;