Add Qt4 windowport

Originally by Ray Chason for 3.4.3, based on the Qt windowport by
Warwick Allison. The look and feel is mostly the same.

Some improvements over the Qt 3 interface are:

* Panes are resizable
* Full support for IBMgraphics, and walls and corridors are drawn with
  graphical primitives for a continuous appearance no matter what the font
  says
* Lots of irritating glitches fixed
* Menus support proportional fonts correctly

Adding this because the old Qt windowport cannot be compiled on Qt4,
even with Qt3 compatibility stuff.

TODO:
 - background map glyphs
 - status hilites
 - menucolors

win/Qt4/qt4yndlg.h

@@ -0,0 +1,34 @@
+// Copyright (c) Warwick Allison, 1999.
+// Qt4 conversion copyright (c) Ray Chason, 2012-2014.
+// NetHack may be freely redistributed.  See license for details.
+
+// qt4yndlg.h -- yes/no dialog
+
+#ifndef QT4YNDLG_H
+#define QT4YNDLG_H
+
+namespace nethack_qt4 {
+
+class NetHackQtYnDialog : QDialog {
+	Q_OBJECT
+private:
+	QString question;
+	const char* choices;
+	char def;
+	char keypress;
+
+protected:
+	virtual void keyPressEvent(QKeyEvent*);
+
+private slots:
+	void doneItem(int);
+
+public:
+	NetHackQtYnDialog(QWidget *,const QString&,const char*,char);
+
+	char Exec();
+};
+
+} // namespace nethack_qt4
+
+#endif