Start implement new check elements (for both dynamic and static grids). Add dynnamic infinityi scroll to example

druid/extended/dynamic_grid.lua

@@ -220,6 +220,14 @@ function DynamicGrid.get_size(self, border)
 end
 
 
+function DynamicGrid.get_size_for(self, count)
+	return vmath.vector3(
+		self.border.z - self.border.x,
+		self.border.y - self.border.w,
+		0)
+end
+
+
 --- Return grid content borders
 -- @tparam DynamicGrid self
 -- @treturn vector3 The grid content borders