Fixed demo party not clearing the party before adding itself, fixed Pokémon icon renamer/mover not moving shiny Pokémon icons properly, added GameData#Something#keys method

Data/Scripts/020_Debug/003_Debug menus/002_Debug_MenuCommands.rb

@@ -543,6 +543,7 @@ DebugMenuCommands.register("demoparty", {
     for id in species
       party.push(id) if GameData::Species.exists?(id)
     end
+    $Trainer.party.clear
     # Generate Pokémon of each species at level 20
     party.each do |species|
       pkmn = Pokemon.new(species, 20)