add mcl2 support of the mesecons lightstones fork

fixes #9

mesecons/lightstones.lua

@@ -1,28 +1,13 @@
 
--- catch on/off events from lightstones
-local lightstone_colors = {
-    "red",
-    "green",
-    "blue",
-    "gray",
-    "darkgray",
-    "yellow",
-    "orange",
-    "white",
-    "pink",
-    "magenta",
-    "cyan",
-    "violet"
-}
-
-for _, color in ipairs(lightstone_colors) do
-    local on_nodename = "mesecons_lightstone:lightstone_" .. color .. "_on"
-    local off_nodename = "mesecons_lightstone:lightstone_" .. color .. "_off"
+local function register(on_nodename, off_nodename)
+    local def_on = minetest.registered_nodes[on_nodename]
+    if not def_on then
+        return
+    end
 
     mtui.mesecons.allowed_nodes[on_nodename] = true
     mtui.mesecons.allowed_nodes[off_nodename] = true
 
-    local def_on = assert(minetest.registered_nodes[on_nodename])
     local old_action_off = assert(def_on.mesecons.effector.action_off)
     def_on.mesecons.effector.action_off = function(pos, node)
         mtui.send_command({
@@ -50,3 +35,28 @@ for _, color in ipairs(lightstone_colors) do
         return old_action_on(pos, node)
     end
 end
+
+-- catch on/off events from lightstones
+local lightstone_colors = {
+    "red",
+    "green",
+    "blue",
+    "gray",
+    "darkgray",
+    "yellow",
+    "orange",
+    "white",
+    "pink",
+    "magenta",
+    "cyan",
+    "violet"
+}
+
+for _, color in ipairs(lightstone_colors) do
+    local on_nodename = "mesecons_lightstone:lightstone_" .. color .. "_on"
+    local off_nodename = "mesecons_lightstone:lightstone_" .. color .. "_off"
+    register(on_nodename, off_nodename)
+end
+
+-- mcl2 fork of mesecons
+register("mesecons_lightstone:lightstone_on", "mesecons_lightstone:lightstone_off")