Refresh price feed to make sure we have data for current local currency

src/mainwindow.cpp

@@ -1343,6 +1343,8 @@ void MainWindow::slot_change_currency(const std::string& currency_name)
 {
     qDebug() << "slot_change_currency"; //<< ": " << currency_name;
     Settings::getInstance()->set_currency_name(currency_name);
+    qDebug() << "Refreshing price stats after currency change";
+    rpc->refreshPrice();
 
     // Include currency
     std::string saved_currency_name;

src/settings.cpp

@@ -323,6 +323,7 @@ QString Settings::getDonationAddr() {
     if (Settings::getInstance()->isTestnet())  {
 	    return "ztestsaplingXXX";
     }
+    // This is used for user feedback
     return "zs1aq4xnrkjlnxx0zesqye7jz3dfrf3rjh7q5z6u8l6mwyqqaam3gx3j2fkqakp33v93yavq46j83q";
 }