FIX: Fixed missing initialization of 'n_activation_function_parameters' variable in constructors.

src/Neuron/NeuronLogistic.cpp

@@ -7,6 +7,7 @@
 
 NeuronLogistic::NeuronLogistic(double a, double b) {
 
+    this->n_activation_function_parameters = 2;
     this->activation_function_parameters = new double[2];
 
     this->activation_function_parameters[0] = a;

src/Neuron/NeuronTanh.cpp

@@ -6,6 +6,7 @@
 
 NeuronTanh::NeuronTanh(double a) {
 
+    this->n_activation_function_parameters = 1;
     this->activation_function_parameters = new double[1];
     this->activation_function_parameters[0] = a;