Add BIP70 deprecation warning

src/qt/paymentserver.cpp

@@ -295,6 +295,9 @@ void PaymentServer::handleURIOrFile(const QString& s)
         if (uri.hasQueryItem("r")) // payment request URI
         {
 #ifdef ENABLE_BIP70
+            Q_EMIT message(tr("URI handling"),
+                tr("You are using a BIP70 URL which will be unsupported in the future."),
+                CClientUIInterface::ICON_WARNING);
             QByteArray temp;
             temp.append(uri.queryItemValue("r"));
             QString decoded = QUrl::fromPercentEncoding(temp);