Allow rescan RPC to take an optional height

src/rpc.cpp

@@ -135,15 +135,17 @@ QJsonValue RPC::makePayload(QString method) {
     return payload;
 }
 
+//TODO: we can use listaddresses
 void RPC::getTAddresses(const std::function<void(QJsonValue)>& cb) {
     QString method = "getaddressesbyaccount";
     QString params = "";
     conn->doRPCWithDefaultErrorHandling(makePayload(method, ""), cb);
 }
 
-void RPC::rescan(const std::function<void(QJsonValue)>& cb) {
+// full or partial rescan
+void RPC::rescan(qint64 height, const std::function<void(QJsonValue)>& cb) {
     QString method = "rescan";
-    conn->doRPCWithDefaultErrorHandling(makePayload(method), cb);
+    conn->doRPCWithDefaultErrorHandling(makePayload(method, QString::number(height)), cb);
 }
 
 void RPC::getZAddresses(const std::function<void(QJsonValue)>& cb) {

src/rpc.h

@@ -138,7 +138,7 @@ private:
     void getPeerInfo            (const std::function<void(QJsonValue)>& cb);
     void getZAddresses          (const std::function<void(QJsonValue)>& cb);
     void getTAddresses          (const std::function<void(QJsonValue)>& cb);
-    void rescan                 (const std::function<void(QJsonValue)>& cb);
+    void rescan                 (qint64 height, const std::function<void(QJsonValue)>& cb);
 
     Connection*                 conn                        = nullptr;
     std::shared_ptr<QProcess>   ehushd                      = nullptr;