Remove zip release files, move mod to root, exclude assets from Makefile

Makefile

@@ -1,4 +1,4 @@
 tarball: clean
-	which zip && zip -r advtrains.zip advtrains
+	which zip && zip -r advtrains.zip . -x "assets*" -x "*.zip" -x "*.git*"
 clean:
 	rm -f advtrains.zip

advtrains/description.txt

@@ -1,8 +1,8 @@
-Advanced Trains v1.3.0, by orwell and contributors. Also see readme.
+Advanced Trains v1.3.8, by orwell and contributors. Also see readme.
 Good-looking, realistic trains for minetest.
 
 For crafting recipes, see manual.pdf
 
 Website: http://advtrains.bleipb.de/
 Manual:  https://github.com/orwell96/advtrains/blob/master/manual.pdf
-Forum :  https://forum.minetest.net/viewtopic.php?f=11&t=14726
+Forum :  https://forum.minetest.net/viewtopic.php?f=11&t=14726

advtrains/init.lua

@@ -382,5 +382,19 @@ minetest.register_chatcommand("at_empty_seats",
 				reload_saves()
 			end)
         end,
-        privs = {train_operator=true}, -- Require the "privs" privilege to run
-    })
+})
+-- This chat command solves another problem: Trains getting randomly stuck.
+minetest.register_chatcommand("at_reroute",
+	{
+        params = "", 
+        description = "Delete all train routes, force them to recalculate", 
+        privs = {train_operator=true}, -- Only train operator is required, since this is relatively safe.
+        func = function(name, param)
+			return advtrains.pcall(function()
+				atwarn("Train routes will be recalculated now")
+				advtrains.save(false)
+				reload_saves()
+			end)
+        end,
+})
+