0027398: Integrate Qt Browser Widget to Open CASCADE Technology

The following implementation has been made:
- CMake procedure is extended to compile Qt tools. This is optional and is handled by USE_QT_TOOLS option(OFF by default)
- It is possible to build Qt tools using Qt5 or Qt4, it is settled with USE_QT4 option.
- Sample of DFBrowser tool is available in samples/tools/TInspectorEXE. It is build with tools, executable is placed in binaries. To start the sample, use dfbrowser.bat command.
- DFBrowser tool may be started from DRAW

tools/DFBrowser/DFBrowser_TreeLevelLineDelegate.cxx

@@ -0,0 +1,52 @@
+// Created on: 2017-06-16
+// Created by: Natalia ERMOLAEVA
+// Copyright (c) 2017 OPEN CASCADE SAS
+//
+// This file is part of Open CASCADE Technology software library.
+//
+// This library is free software; you can redistribute it and/or modify it under
+// the terms of the GNU Lesser General Public License version 2.1 as published
+// by the Free Software Foundation, with special exception defined in the file
+// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
+// distribution for complete text of the license and disclaimer of any warranty.
+//
+// Alternatively, this file may be used under the terms of Open CASCADE
+// commercial license or contractual agreement. 
+
+#include <DFBrowser_TreeLevelLineDelegate.hxx>
+#include <DFBrowser_Window.hxx>
+
+#include <QPainter>
+
+// =======================================================================
+// function : Constructor
+// purpose :
+// =======================================================================
+DFBrowser_TreeLevelLineDelegate::DFBrowser_TreeLevelLineDelegate (QObject* theParent)
+: QItemDelegate (theParent)
+{
+}
+
+// =======================================================================
+// function : paint
+// purpose :
+// =======================================================================
+void DFBrowser_TreeLevelLineDelegate::paint (QPainter* thePainter, const QStyleOptionViewItem& theOption,
+                                             const QModelIndex& theIndex) const
+{
+  // highlight cell
+  if (theOption.state & QStyle::State_MouseOver)
+    thePainter->fillRect (theOption.rect, DFBrowser_Window::LightHighlightColor());
+
+  // action icon for all indices before the last one
+  if (theIndex.column() < theIndex.model()->columnCount()-1)
+  {
+    QIcon anIcon (":/icons/level_change.png");
+    QSize anIconSize (10, 20);
+    thePainter->drawPixmap (QRect (theOption.rect.right() - anIconSize.width(), theOption.rect.top(),
+                                   anIconSize.width(), anIconSize.height()),
+                            anIcon.pixmap (anIconSize.width(), anIconSize.height()));
+  }
+  // default paint
+  QItemDelegate::paint (thePainter, theOption, theIndex);
+}