wrong comment correction (#800)

Author: SamuelBellomo

Assets/Scripts/Gameplay/GameplayObjects/IDamageable.cs

@@ -14,7 +14,7 @@ public interface IDamageable
         /// Receives HP damage or healing.
         /// </summary>
         /// <param name="inflicter">The Character responsible for the damage. May be null.</param>
-        /// <param name="HP">The damage done. Positive value is damage, negative is healing.</param>
+        /// <param name="HP">The damage done. Negative value is damage, positive is healing.</param>
         void ReceiveHP(ServerCharacter inflicter, int HP);
 
         /// <summary>