(2) For the purposes of subsection (1), a person shall be deemed to have commenced the development of land until the contrary is proved, the burden of which shall lie on any person charged, if that person commenced the laying out of roads, the laying of water pipes, the clearing of or levelling of land, the filling of ravines or swamps, the construction of any building or any preparatory work which might indicate an intention thereby to improve the land or increase its value or make it in any way ready for any type of development, except those to which section 18 applies.