citra_qt: Add Game List configuration

This adds a Game List configuration group box which is similar to yuzu's, with features including icon size setting, row 1/2 text, and ability to hide invalid titles (those without a valid SMDH). I also added a UI tab and moved the language and theme settings there.

src/citra_qt/configuration/configure_ui.h

@@ -0,0 +1,34 @@
+// Copyright 2018 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <memory>
+#include <QWidget>
+
+namespace Ui {
+class ConfigureUi;
+}
+
+class ConfigureUi : public QWidget {
+    Q_OBJECT
+
+public:
+    explicit ConfigureUi(QWidget* parent = nullptr);
+    ~ConfigureUi();
+
+    void applyConfiguration();
+    void retranslateUi();
+
+private slots:
+    void onLanguageChanged(int index);
+
+signals:
+    void languageChanged(const QString& locale);
+
+private:
+    void setConfiguration();
+
+    std::unique_ptr<Ui::ConfigureUi> ui;
+};