Row.c: use luaL to check argument types
Row.c: use luaL to check argument types

and set type name of metatable for Row to
"npge_model_cRow" to distinguish it from other userdata.

starius/lua-npge,starius/lua-npge,npge/lua-npge,npge/lua-npge,starius/lua-npge,npge/lua-npge