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_plot_scaleitem.h

@@ -0,0 +1,94 @@
+/* -*- 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_PLOT_SCALE_ITEM_H
+#define QWT_PLOT_SCALE_ITEM_H
+
+#include "qwt_global.h"
+#include "qwt_plot_item.h"
+#include "qwt_scale_draw.h"
+
+class QPalette;
+
+/*!
+  \brief A class which draws a scale inside the plot canvas
+
+  QwtPlotScaleItem can be used to draw an axis inside the plot canvas.
+  It might by synchronized to one of the axis of the plot, but can
+  also display its own ticks and labels.
+
+  It is allowed to synchronize the scale item with a disabled axis.
+  In plots with vertical and horizontal scale items, it might be
+  necessary to remove ticks at the intersections, by overloading
+  updateScaleDiv().
+
+  The scale might be at a specific position (f.e 0.0) or it might be
+  aligned to a canvas border.
+
+  \par Example
+    The following example shows how to replace the left axis, by a scale item
+    at the x position 0.0.
+    \code
+      QwtPlotScaleItem *scaleItem = new QwtPlotScaleItem( QwtScaleDraw::RightScale, 0.0 );
+      scaleItem->setFont( plot->axisWidget( QwtPlot::yLeft )->font() );
+      scaleItem->attach(plot);
+
+      plot->enableAxis( QwtPlot::yLeft, false );
+    \endcode
+  \endpar
+*/
+
+class QWT_EXPORT QwtPlotScaleItem: public QwtPlotItem
+{
+public:
+    explicit QwtPlotScaleItem(
+        QwtScaleDraw::Alignment = QwtScaleDraw::BottomScale,
+        const double pos = 0.0 );
+
+    virtual ~QwtPlotScaleItem();
+
+    virtual int rtti() const;
+
+    void setScaleDiv( const QwtScaleDiv& );
+    const QwtScaleDiv& scaleDiv() const;
+
+    void setScaleDivFromAxis( bool on );
+    bool isScaleDivFromAxis() const;
+
+    void setPalette( const QPalette & );
+    QPalette palette() const;
+
+    void setFont( const QFont& );
+    QFont font() const;
+
+    void setScaleDraw( QwtScaleDraw * );
+
+    const QwtScaleDraw *scaleDraw() const;
+    QwtScaleDraw *scaleDraw();
+
+    void setPosition( double pos );
+    double position() const;
+
+    void setBorderDistance( int );
+    int borderDistance() const;
+
+    void setAlignment( QwtScaleDraw::Alignment );
+
+    virtual void draw( QPainter *,
+        const QwtScaleMap &xMap, const QwtScaleMap &yMap,
+        const QRectF &canvasRect ) const;
+
+    virtual void updateScaleDiv( const QwtScaleDiv &, const QwtScaleDiv & );
+
+private:
+    class PrivateData;
+    PrivateData *d_data;
+};
+
+#endif