message: Hide Import Addr button until user decrypts a key
diff: @@ -73,6 +73,7 @@ SettingsBitToolWidget::SettingsBitToolWidget(PIVXGUI* _window, QWidget *parent)
  ui->pushButtonImport->setText(tr("Import Address"));
  setCssProperty(ui->pushButtonImport, "btn-text-primary");
  + ui->pushButtonImport->setVisible(false);
  connect(ui->pushLeft, &QPushButton::clicked, [this](){onEncryptSelected(true);});
  connect(ui->pushRight, &QPushButton::clicked, [this](){onEncryptSelected(false);});
  @@ -270,6 +271,7 @@ void SettingsBitToolWidget::onClearDecrypt()
  ui->lineEditKey->clear();
  ui->lineEditDecryptResult->clear();
  ui->lineEditPassphrase->clear();
  + ui->pushButtonImport->setVisible(false);
  key = CKey();
  }
  @@ -290,6 +292,7 @@ void SettingsBitToolWidget::onDecryptClicked()
  CPubKey pubKey = key.GetPubKey();
  CBitcoinAddress address(pubKey.GetID());
  ui->lineEditDecryptResult->setText(QString::fromStdString(address.ToString()));
  + ui->pushButtonImport->setVisible(true);
  }
  void SettingsBitToolWidget::importAddressFromDecKey()
  