add QAD::VirtualKeyboard library, vkbd for widgets with JSON-based description

libs/virtual_keyboard/plugin/virtual_keyboard_plugin.h

@@ -0,0 +1,36 @@
+#ifndef virtual_keyboard_plugin_h
+#define virtual_keyboard_plugin_h
+
+#include <QObject>
+#if QT_VERSION >= 0x050000
+#  include <QtUiPlugin/QDesignerCustomWidgetInterface>
+#else
+#  include <QDesignerCustomWidgetInterface>
+#endif
+
+class VirtualKeyboardPlugin
+	: public QObject
+	, public QDesignerCustomWidgetInterface {
+	Q_OBJECT
+	Q_INTERFACES(QDesignerCustomWidgetInterface)
+
+public:
+	VirtualKeyboardPlugin(QObject * parent = 0);
+
+	bool isContainer() const;
+	bool isInitialized() const;
+	QIcon icon() const;
+	QString domXml() const;
+	QString group() const;
+	QString includeFile() const;
+	QString name() const;
+	QString toolTip() const;
+	QString whatsThis() const;
+	QWidget * createWidget(QWidget * parent);
+	void initialize(QDesignerFormEditorInterface * core);
+
+private:
+	bool m_initialized;
+};
+
+#endif