[CHANGE] widget margins used to be around 5-10 pixel wide as they were not...

[CHANGE] widget margins used to be around 5-10 pixel wide as they were not set. This shrinks them to 1px which seems to be reasonable on OSX at least.
If this does not work on other platforms, please introduce platform-specific layout choices.

src/qt4gui/qt4/WQtGLDockWidget.cpp

@@ -41,6 +41,7 @@ WQtGLDockWidget::WQtGLDockWidget( QString viewTitle, QString dockTitle, QWidget*
     // This allows adding other widgets to certain docks
     m_panel = new QWidget( this );
     m_layout = new QVBoxLayout();
+    m_layout->setContentsMargins( 1, 1, 1, 1 );
 
     m_glWidget = boost::shared_ptr<WQtGLWidget>( new WQtGLWidget( viewTitle.toStdString(), m_panel, projectionMode, shareWidget ) );