add FlatButton constructors

flatbutton.cpp

@@ -0,0 +1,16 @@
+#include "flatbutton.h"
+
+FlatButton::FlatButton(QWidget *parent)
+    : QAbstractButton(parent)
+{
+}
+
+FlatButton::FlatButton(const QString &text, QWidget *parent)
+    : QAbstractButton(parent)
+{
+    setText(text);
+}
+
+FlatButton::~FlatButton()
+{
+}

flatbutton.h

@@ -0,0 +1,16 @@
+#ifndef FLATBUTTON_H
+#define FLATBUTTON_H
+
+#include <QAbstractButton>
+
+class FlatButton : public QAbstractButton
+{
+    Q_OBJECT
+
+public:
+    explicit FlatButton(QWidget *parent = 0);
+    explicit FlatButton(const QString &text, QWidget *parent = 0);
+    ~FlatButton();
+};
+
+#endif // FLATBUTTON_H