compute_next_timestep():

Restrict time-step-list when time-limit has been reached: +/-_button
	does not move upward anymore.

library/src/calculate_price.cpp

@@ -484,6 +484,15 @@ int CALCULATE_LIBRARY_API compute_next_timestep(parking_tariff_t *tariff, int cu
     qCritical() << __LINE__ << "compute_next_timestep()     currentTimeMinutes: " << currentTimeMinutes;
     qCritical() << __LINE__ << "compute_next_timestep() up/down (1=up, 0=down): " << UpDown;
 
+    if (UpDown == 1) {
+        if (Calculator::GetInstance().timeLimitReached()) {
+            qCritical() << __LINE__ << "compute_next_timestep() time limit reached";
+            Calculator::GetInstance().setTimeLimitReached(false);
+            Calculator::GetInstance().resetCostAtTimeLimit();
+            return currentTimeMinutes;
+        }
+    }
+
     // FIXME
     //std::optional<ATBPaymentOption> paymentOption = tariff->getPaymentOptionForKey(permitType.get());
     //if (!paymentOption.has_value()) {