Qt5 built in qwt (#570)

- qt4->qt5
- in built qt5 6.1.5 because rhel7 is not upto date with qt5, removed findqwt.cmake
- made a fix in qwt lib (qwt_plot_layout.h) to work with 5.15 and lower versions for qrect constr.
- qt5 forms fixed, qt4 many hard coding forms switched to forms including qtabwidget, scrolls etc, fonts moved to forms
 - docking option enabled by default, removed option to disable docking feature from "Mode"
- added qVersionResolve utility functions to handle compatibility before and after qt5.12
- qtplots (ian's code) takes in gain mode enable to set some settings within the class, with proper gain plot ticks
- ensure gain plots have no zooming of z axis in 2d and y axis in 1d
- removed placeholder text in qpalette in main window form as its not supportd until 5.12 (so using qt5.9 designer insted of qt5.15 to cope)
- tab order
Servers:
- fixed some error messages that were empty for fail in funcs (mostly minor as if this error, major issues)

libs/qwt-6.1.5/include/qwt_magnifier.h

@@ -0,0 +1,86 @@
+/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
+ * Qwt Widget Library
+ * Copyright (C) 1997   Josef Wilgen
+ * Copyright (C) 2002   Uwe Rathmann
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the Qwt License, Version 1.0
+ *****************************************************************************/
+
+#ifndef QWT_MAGNIFIER_H
+#define QWT_MAGNIFIER_H 1
+
+#include "qwt_global.h"
+#include <qobject.h>
+
+class QWidget;
+class QMouseEvent;
+class QWheelEvent;
+class QKeyEvent;
+
+/*!
+  \brief QwtMagnifier provides zooming, by magnifying in steps.
+
+  Using QwtMagnifier a plot can be zoomed in/out in steps using
+  keys, the mouse wheel or moving a mouse button in vertical direction.
+*/
+class QWT_EXPORT QwtMagnifier: public QObject
+{
+    Q_OBJECT
+
+public:
+    explicit QwtMagnifier( QWidget * );
+    virtual ~QwtMagnifier();
+
+    QWidget *parentWidget();
+    const QWidget *parentWidget() const;
+
+    void setEnabled( bool );
+    bool isEnabled() const;
+
+    // mouse
+    void setMouseFactor( double );
+    double mouseFactor() const;
+
+    void setMouseButton( Qt::MouseButton, Qt::KeyboardModifiers = Qt::NoModifier );
+    void getMouseButton( Qt::MouseButton &, Qt::KeyboardModifiers & ) const;
+
+    // mouse wheel
+    void setWheelFactor( double );
+    double wheelFactor() const;
+
+    void setWheelModifiers( Qt::KeyboardModifiers );
+    Qt::KeyboardModifiers wheelModifiers() const;
+
+    // keyboard
+    void setKeyFactor( double );
+    double keyFactor() const;
+
+    void setZoomInKey( int key, Qt::KeyboardModifiers = Qt::NoModifier );
+    void getZoomInKey( int &key, Qt::KeyboardModifiers & ) const;
+
+    void setZoomOutKey( int key, Qt::KeyboardModifiers = Qt::NoModifier );
+    void getZoomOutKey( int &key, Qt::KeyboardModifiers & ) const;
+
+    virtual bool eventFilter( QObject *, QEvent * );
+
+protected:
+    /*!
+       Rescale the parent widget
+       \param factor Scale factor
+     */
+    virtual void rescale( double factor ) = 0;
+
+    virtual void widgetMousePressEvent( QMouseEvent * );
+    virtual void widgetMouseReleaseEvent( QMouseEvent * );
+    virtual void widgetMouseMoveEvent( QMouseEvent * );
+    virtual void widgetWheelEvent( QWheelEvent * );
+    virtual void widgetKeyPressEvent( QKeyEvent * );
+    virtual void widgetKeyReleaseEvent( QKeyEvent * );
+
+private:
+    class PrivateData;
+    PrivateData *d_data;
+};
+
+#endif