add same functionality as 2.4

apps/traincascade/cascadeclassifier.cpp

@@ -168,6 +168,13 @@ bool CvCascadeClassifier::train( const string _cascadeDirName,
         featureEvaluator = CvFeatureEvaluator::create(cascadeParams.featureType);
         featureEvaluator->init( featureParams, numPos + numNeg, cascadeParams.winSize );
         stageClassifiers.reserve( numStages );
+    }else{
+        // Make sure that if model parameters are preloaded, that people are aware of this,
+        // even when passing other parameters to the training command
+        cout << "---------------------------------------------------------------------------------" << endl;
+        cout << "Training parameters are pre-loaded from the parameter file in data folder!" << endl;
+        cout << "Please empty this folder if you want to use a NEW set of training parameters." << endl;
+        cout << "---------------------------------------------------------------------------------" << endl;
     }
     cout << "PARAMETERS:" << endl;
     cout << "cascadeDirName: " << _cascadeDirName << endl;