Reducing the amount of config confusion for retro mode

This is to avoid confusion, if you want this kind of customization I'll add it in but disassociate it with retro mode.

src/main/resources/config.yml

@@ -8,17 +8,11 @@
 #  Settings for mcMMO in general
 ###
 General:
-    Skill_Scaling:
         # Turning this on will scale mcMMO around 1-1000 with default scaling factor
         # Everything in your config related to skill level requirements, skill level bonuses, etc will be multiplied by 10 when this mode is on
         # This change is purely cosmetic, it retains the old feel of mcMMO where you could level up thousands of times
-        RetroMode: true
-        Skill_Scaling:
-            # This is the value that is skill level requirements are multiplied by in Retro Mode (Default is 10)
-            RetroMode_LevelReq_Factor: 10
-            # This is the value that the xp required to level is multiplied by when in Retro mode
-            # Default is 1
-            RetroMode_XP_Formula_Factor: 1
+        RetroMode:
+            Enabled: true
     Locale: en_US
     MOTD_Enabled: true
     # Send a message to the player when his profile was successfully loaded