Remove out-commented code

dune/grid/common/defaultgridview.hh

@@ -102,21 +102,6 @@ namespace Dune
         level_( level )
     {}
 
-    // use default implementation of copy constructor and assignment operator
-#if 0
-    DefaultLevelGridView ( const ThisType &other )
-      : grid_( other.grid_ ),
-        level_( other.level_ )
-    {}
-
-    /** \brief assignment from other GridView on the same grid */
-    ThisType &operator= ( const ThisType & other)
-    {
-      grid_ = other.grid_;
-      level_ = other.level_;
-    }
-#endif
-
     /** \brief obtain a const reference to the underlying hierarchic grid */
     const Grid &grid () const
     {