message: [UI] Persist receive address through wallet restart
diff: #include <QMessageBox>
  #include <QScrollBar>
  #include <QTextDocument>
  +#include <QSettings>
  ReceiveCoinsDialog::ReceiveCoinsDialog(QWidget* parent) : QDialog(parent, Qt::WindowSystemMenuHint | Qt::WindowTitleHint | Qt::WindowCloseButtonHint),
  ui(new Ui::ReceiveCoinsDialog),
  @@ -86,6 +87,9 @@ void ReceiveCoinsDialog::setModel(WalletModel* model)
  columnResizingFixer = new GUIUtil::TableViewLastColumnResizingFixer(tableView, AMOUNT_MINIMUM_COLUMN_WIDTH, DATE_COLUMN_WIDTH);
  // Init address field
  + QSettings settings;
  + address = settings.value("current_receive_address").toString();
  + if (address.isEmpty())
  address = getAddress();
  ui->reqAddress->setText(address);
  @@ -95,13 +99,14 @@ void ReceiveCoinsDialog::setModel(WalletModel* model)
  ReceiveCoinsDialog::~ReceiveCoinsDialog()
  {
  + QSettings settings;
  + settings.setValue("current_receive_address", address);
  delete ui;
  }
  void ReceiveCoinsDialog::clear()
  {
  ui->reqAmount->clear();
  - address = getAddress();
  ui->reqAddress->setText(address);
  ui->reqLabel->setText("");
  ui->reqMessage->setText("");
  @@ -290,7 +295,8 @@ void ReceiveCoinsDialog::copyAddress()
  void ReceiveCoinsDialog::receiveAddressUsed()
  {
  - if (model && model->isUsed(CBitcoinAddress(address.toStdString()))) {
  + if ((!ui->reuseAddress->isChecked()) && model && model->isUsed(CBitcoinAddress(address.toStdString()))) {
  + address = getAddress();
  clear();
  }
  }
  