Use persistent hash for config

lib/states/game_states/game.rb

@@ -40,9 +40,9 @@ class IMICFPS
 
       @camera.update
 
-      if $debug.get(:stats)
+      if window.config.get(:debug_options, :stats)
         @text.text = update_text
-      elsif $debug.get(:fps)
+      elsif window.config.get(:options, :fps)
         @text.text = "FPS: #{Gosu.fps}"
       else
         @text.text = ""

lib/states/game_states/loading_state.rb

@@ -55,7 +55,7 @@ class IMICFPS
         when :model
           ModelLoader.new(manifest: hash[:manifest], entity: @dummy_entity)
         when :shader
-          if $debug.get(:use_shaders)
+          if window.config.get(:debug_options, :use_shaders)
             shader = Shader.new(name: hash[:name], includes_dir: "shaders/include", vertex: "shaders/vertex/#{hash[:name]}.glsl", fragment: "shaders/fragment/#{hash[:name]}.glsl")
           else
             warn "Skipping shader: #{hash[:name]}..."