FIX: Removing max and min values after de-normalization of data-set, so the...

FIX: Removing max and min values after de-normalization of data-set, so the is_normalized() method will again return 'False' after de-normalization.

src/DataSet/DataSet.cpp

@@ -368,6 +368,9 @@ namespace lib4neuro {
             }
             pair.second = tmp_out;
         }
+
+        /* Remove found max and minimal values, because of is_normalized() method */
+        this->max_min_inp_val.clear();
     }
 
     void DataSet::de_normalize_single(std::vector<double> &d1, std::vector<double> &d2){