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_date_scale_draw.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_DATE_SCALE_DRAW_H_
+#define _QWT_DATE_SCALE_DRAW_H_ 1
+
+#include "qwt_global.h"
+#include "qwt_scale_draw.h"
+#include "qwt_date.h"
+
+/*!
+  \brief A class for drawing datetime scales
+
+  QwtDateScaleDraw displays values as datetime labels.
+  The format of the labels depends on the alignment of
+  the major tick labels.
+
+  The default format strings are:
+
+  - Millisecond\n
+    "hh:mm:ss:zzz\nddd dd MMM yyyy"
+  - Second\n
+    "hh:mm:ss\nddd dd MMM yyyy"
+  - Minute\n
+    "hh:mm\nddd dd MMM yyyy"
+  - Hour\n
+    "hh:mm\nddd dd MMM yyyy"
+  - Day\n
+    "ddd dd MMM yyyy"
+  - Week\n
+    "Www yyyy"
+  - Month\n
+    "MMM yyyy"
+  - Year\n
+    "yyyy"
+
+  The format strings can be modified using setDateFormat()
+  or individually for each tick label by overloading dateFormatOfDate(),
+
+  Usually QwtDateScaleDraw is used in combination with
+  QwtDateScaleEngine, that calculates scales for datetime
+  intervals.
+
+  \sa QwtDateScaleEngine, QwtPlot::setAxisScaleDraw()
+*/
+class QWT_EXPORT QwtDateScaleDraw: public QwtScaleDraw
+{
+public:
+    QwtDateScaleDraw( Qt::TimeSpec = Qt::LocalTime );
+    virtual ~QwtDateScaleDraw();
+
+    void setDateFormat( QwtDate::IntervalType, const QString & );
+    QString dateFormat( QwtDate::IntervalType ) const;
+
+    void setTimeSpec( Qt::TimeSpec );
+    Qt::TimeSpec timeSpec() const;
+
+    void setUtcOffset( int seconds );
+    int utcOffset() const;
+
+    void setWeek0Type( QwtDate::Week0Type );
+    QwtDate::Week0Type week0Type() const;
+
+    virtual QwtText label( double ) const;
+
+    QDateTime toDateTime( double ) const;
+
+protected:
+    virtual QwtDate::IntervalType
+        intervalType( const QwtScaleDiv & ) const;
+
+    virtual QString dateFormatOfDate( const QDateTime &,
+        QwtDate::IntervalType ) const;
+
+private:
+    class PrivateData;
+    PrivateData *d_data;
+};
+
+#endif