fix obsolete fonctions

src/gridview.cpp

@@ -300,7 +300,7 @@ GridView::GridView(QWidget *parent)
     info_layout->addWidget(m_mouse_pos_label);
     info_layout->addWidget(new QLabel("Left click : edit; Right click : select; F11 for fullscreen mode", this));
     info_layout->addWidget(new QLabel("Hold SHIFT to move across the grid; Scroll wheel or CTRL+/CTRL- to zoom", this));
-    info_layout->setMargin(0);
+    info_layout->setContentsMargins(0,0,0,0);
     m_info_section->setLayout(info_layout);
 
     layout->addWidget(m_info_section);

src/src.pro

 QT       += core gui
 
-greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
+greaterThan(QT_MAJOR_VERSION, 4):
+QT += widgets
 qtHaveModule(multimedia): DEFINES += HAS_MULTIMEDIA
 qtHaveModule(multimedia): QT += multimedia
-}
+
 
 CONFIG += c++14
 TEMPLATE = app