Pathfinding: Remove Jumper submodule.

Tidy-up init.lua
Update Readme.

init.lua

@@ -1,30 +1,6 @@
 -- Advanced NPC mod by Zorman2000
 local path = minetest.get_modpath("advanced_npc")
 
--- Below code for require is taken and slightly modified
--- from irc mod by Diego Martinez (kaeza)
--- https://github.com/minetest-mods/irc
--- Handle mod security if needed
--- local ie = minetest.request_insecure_environment()
--- -- local req_ie = minetest.request_insecure_environment()
--- -- if req_ie then 
--- --   ie = req_ie 
--- -- end
--- if not ie then
---   error("The Advanced NPC mod requires access to insecure functions in "..
---     "order to work.  Please add the Advanced NPC mod to the "..
---     "secure.trusted_mods setting or disable the mod.")
--- end
-
--- -- Modify package path so that it can find the Jumper library files
--- ie.package.path = 
---   path .. "/Jumper/?.lua;"..
---   ie.package.path
-
--- -- Require the main files from Jumper
--- Grid = ie.require("jumper.grid")
--- Pathfinder = ie.require("jumper.pathfinder")
-
 -- Intllib
 local S
 if minetest.get_modpath("intllib") then