Added Clearing Hotkeys+Displays

-Added Clearing:
-- HotkeyList.
--PersistentList
--CavebotList
--Hud DisplayList

-Also added a new way of deleting nodes (the if not nil, finish(),
.pause/resume etc...

-TO DO: I'll start tomorrow the Lua Sandbox, after done I'll finish the
Script Editor look-like Neobot.