Adding #include <QUrl> in MainWindowImpl.cpp (forward declaration)

[alainpannetier]

This might be a consequence of qt4 version but I had to add this include in MainWindowImpl.cpp

#include "MainWindowImpl.h"
#include "LibrariesInfo.h"
#include <QTimer>
#include <QStandardItemModel>
#include <QFileInfo>
#include <QFileDialog>
#include <QMessageBox>
#include <QDragEnterEvent>
#include <QMimeData>
#include <QUrl>                  //  <--- New


const char *versionString = "1.0";

Otherwise, you get this kind of messages at make time

../MainWindowImpl.cpp:208:24: error: invalid use of incomplete type ‘class QUrl’
     openFile(urls.first().toLocalFile());  
    ~~~~~~~~~~^~