save owner from bones

partially attends to https://github.com/minetest-mapserver/mapserver/issues/72

bones.lua

+-- bones owner saving workaround
+-- https://github.com/minetest/minetest_game/blob/master/mods/bones/init.lua#L120
+
+local bones_def = minetest.registered_items["bones:bones"]
+assert(bones_def)
+
+local bones_on_timer = bones_def.on_timer
+assert(bones_on_timer)
+assert(type(bones_on_timer) == "function")
+
+minetest.override_item("bones:bones", {
+	on_timer = function(pos, elapsed)
+		-- save owner in separate field
+		local meta = minetest.get_meta(pos)
+		meta:set_string("_owner", meta:get_string("owner"))
+
+		-- call original function
+		bones_on_timer(pos, elapsed)
+	end
+})

init.lua

@@ -17,6 +17,10 @@ dofile(MP.."/privs.lua")
 dofile(MP.."/show_waypoint.lua")
 dofile(MP.."/search.lua")
 
+if minetest.get_modpath("bones") then
+	dofile(MP.."/bones.lua")
+end
+
 
 -- optional mapserver-bridge stuff below
 local http = minetest.request_http_api()

mod.conf

 name = mapserver
 description = Mod for the mapserver.
-optional_depends = default, dye, advtrains, minecart, monitoring
+optional_depends = default, dye, advtrains, minecart, monitoring, bones