[GL] Grid; Explicitly delete copy and op=

GeoLib/Grid.h

@@ -52,6 +52,9 @@ public:
     Grid(InputIterator first, InputIterator last,
          std::size_t max_num_per_grid_cell = 512);
 
+    Grid(Grid const&) = delete;
+    Grid& operator=(Grid const&) = delete;
+
     /**
      * This is the destructor of the class. It deletes the internal data
      * structures *not* including the pointers to the points.