fix: Updates races to properly support gargoyle equipment. (#744)

* Adds `RaceFlag` to the `Race` object. This is `1 << RaceIndex`
* Replaces `RequiredRace`  with `RequiredRaces` for items.
* Adds convenience flags for `RequiredRaces`
  ```cs
  
  public const int AllowAllRaces = 0x7;      // Race.Human.RaceFlag | Race.Elf.RaceFlag | Race.Gargoyle.RaceFlag
  public const int AllowHumanOrElves = 0x3;  // Race.Human.RaceFlag | Race.Elf.RaceFlag
  public const int AllowElvesOnly = 0x2;     // Race.Elf.RaceFlag
  public const int AllowGargoylesOnly = 0x4; // Race.Gargoyle.RaceFlag
  ```
* Example usage on an item:
  ```cs
  public override int RequiredRaces => Race.AllowHumanOrElves;
  ```
* Adds Wood and Stone armor material types
* Updates Woodland armor to Wood
* Adds proper messaging for race restrictions
* Adds gargoyle only for object properties
* Adds `CheckRace` functions for validating if a race or mobile can use the item:
  ```cs
  bool CheckRace(Race race);
  bool CheckRace(Mobile from, bool message = true);
  ```

Projects/UOContent/Items/Armor/ArmorEnums.cs

@@ -50,7 +50,9 @@ namespace Server.Items
         Ringmail,
         Chainmail,
         Plate,
-        Dragon // On OSI, Dragon is seen and considered its own type.
+        Dragon,
+        Wood,
+        Stone
     }
 
     public enum ArmorMeditationAllowance