Add CustomPaintWidget and super-super hacky initial 'rendering' test

qrenderdoc/CustomPaintWidget.h

@@ -0,0 +1,22 @@
+#ifndef CUSTOMPAINTWIDGET_H
+#define CUSTOMPAINTWIDGET_H
+
+#include <QWidget>
+
+class CustomPaintWidget : public QWidget
+{
+    Q_OBJECT
+  public:
+    explicit CustomPaintWidget(QWidget *parent = 0);
+    ~CustomPaintWidget();
+
+  signals:
+
+  public slots:
+
+  protected:
+    void paintEvent(QPaintEvent *e);
+    QPaintEngine *paintEngine() const { return NULL; }
+};
+
+#endif // CUSTOMPAINTWIDGET_H