Add new enchants and fallback to bukkit enchant name map

src/main/java/com/gmail/nossr50/util/EnchantmentUtils.java

@@ -31,6 +31,9 @@ public class EnchantmentUtils {
         enchants.put("FLAME", Enchantment.ARROW_FIRE);
         enchants.put("KNOCKBACK", Enchantment.KNOCKBACK);
         enchants.put("THORNS", Enchantment.THORNS);
+        enchants.put("MENDING", Enchantment.MENDING);
+        enchants.put("DEPTH_STRIDER", Enchantment.DEPTH_STRIDER);
+        enchants.put("FROST_WALKER", Enchantment.FROST_WALKER);
     }
 
     /**
@@ -45,6 +48,6 @@ public class EnchantmentUtils {
             return enchants.get(enchantmentName);
         }
 
-        return null;
+        return Enchantment.getByName(enchantmentName);
     }
 }