Add digilines piston

init.lua

@@ -11,6 +11,7 @@ local components = {
 	"piezo",
 	"detector",
 	"conductors",
+	"piston",
 }
 for _,name in ipairs(components) do
 	dofile(string.format("%s%s%s.lua",minetest.get_modpath(minetest.get_current_modname()),DIR_DELIM,name))