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_histogram.h

@@ -0,0 +1,139 @@
+/* -*- 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_HISTOGRAM_H
+#define QWT_PLOT_HISTOGRAM_H
+
+#include "qwt_global.h"
+#include "qwt_plot_seriesitem.h"
+#include "qwt_column_symbol.h"
+#include <qcolor.h>
+#include <qvector.h>
+
+class QwtIntervalData;
+class QString;
+class QPolygonF;
+
+/*!
+  \brief QwtPlotHistogram represents a series of samples, where an interval
+         is associated with a value ( \f$y = f([x1,x2])\f$ ).
+
+  The representation depends on the style() and an optional symbol()
+  that is displayed for each interval.
+
+  \note The term "histogram" is used in a different way in the areas of
+        digital image processing and statistics. Wikipedia introduces the
+        terms "image histogram" and "color histogram" to avoid confusions.
+        While "image histograms" can be displayed by a QwtPlotCurve there
+        is no applicable plot item for a "color histogram" yet.
+
+  \sa QwtPlotBarChart, QwtPlotMultiBarChart
+*/
+
+class QWT_EXPORT QwtPlotHistogram:
+    public QwtPlotSeriesItem, public QwtSeriesStore<QwtIntervalSample>
+{
+public:
+    /*!
+        Histogram styles.
+        The default style is QwtPlotHistogram::Columns.
+
+        \sa setStyle(), style(), setSymbol(), symbol(), setBaseline()
+    */
+    enum HistogramStyle
+    {
+        /*!
+           Draw an outline around the area, that is build by all intervals
+           using the pen() and fill it with the brush(). The outline style
+           requires, that the intervals are in increasing order and
+           not overlapping.
+         */
+        Outline,
+
+        /*!
+           Draw a column for each interval. When a symbol() has been set
+           the symbol is used otherwise the column is displayed as
+           plain rectangle using pen() and brush().
+         */
+        Columns,
+
+        /*!
+           Draw a simple line using the pen() for each interval.
+         */
+        Lines,
+
+        /*!
+           Styles >= UserStyle are reserved for derived
+           classes that overload drawSeries() with
+           additional application specific ways to display a histogram.
+         */
+        UserStyle = 100
+    };
+
+    explicit QwtPlotHistogram( const QString &title = QString() );
+    explicit QwtPlotHistogram( const QwtText &title );
+    virtual ~QwtPlotHistogram();
+
+    virtual int rtti() const;
+
+    void setPen( const QColor &, qreal width = 0.0, Qt::PenStyle = Qt::SolidLine );
+    void setPen( const QPen & );
+    const QPen &pen() const;
+
+    void setBrush( const QBrush & );
+    const QBrush &brush() const;
+
+    void setSamples( const QVector<QwtIntervalSample> & );
+    void setSamples( QwtSeriesData<QwtIntervalSample> * );
+
+    void setBaseline( double );
+    double baseline() const;
+
+    void setStyle( HistogramStyle style );
+    HistogramStyle style() const;
+
+    void setSymbol( const QwtColumnSymbol * );
+    const QwtColumnSymbol *symbol() const;
+
+    virtual void drawSeries( QPainter *,
+        const QwtScaleMap &xMap, const QwtScaleMap &yMap,
+        const QRectF &canvasRect, int from, int to ) const;
+
+    virtual QRectF boundingRect() const;
+
+    virtual QwtGraphic legendIcon( int index, const QSizeF & ) const;
+
+protected:
+    virtual QwtColumnRect columnRect( const QwtIntervalSample &,
+        const QwtScaleMap &, const QwtScaleMap & ) const;
+
+    virtual void drawColumn( QPainter *, const QwtColumnRect &,
+        const QwtIntervalSample & ) const;
+
+    void drawColumns( QPainter *,
+        const QwtScaleMap &xMap, const QwtScaleMap &yMap,
+        int from, int to ) const;
+
+    void drawOutline( QPainter *,
+        const QwtScaleMap &xMap, const QwtScaleMap &yMap,
+        int from, int to ) const;
+
+    void drawLines( QPainter *,
+         const QwtScaleMap &xMap, const QwtScaleMap &yMap,
+         int from, int to ) const;
+
+private:
+    void init();
+    void flushPolygon( QPainter *, double baseLine, QPolygonF & ) const;
+
+    class PrivateData;
+    PrivateData *d_data;
+};
+
+#endif