Restore xml docs and change obsolete message

src/Discord.Net.Core/Entities/Invites/IInviteMetadata.cs

@@ -15,10 +15,14 @@ namespace Discord
         ///     <c>false</c>.
         /// </returns>
         bool IsTemporary { get; }
-
-        [Obsolete("This will always return false. If an invite is revoked, it will not be found and the invite will be null.")]
+        /// <summary>
+        ///     Gets a value that indicates whether the invite has been revoked.
+        /// </summary>
+        /// <returns>
+        ///     <c>true</c> if this invite was revoked; otherwise <c>false</c>.
+        /// </returns>
+        [Obsolete("This property doesn't exist anymore and shouldn't be used.")]
         bool IsRevoked { get; }
-
         /// <summary>
         ///     Gets the time (in seconds) until the invite expires.
         /// </summary>

src/Discord.Net.Rest/API/Common/InviteMetadata.cs

@@ -16,7 +16,5 @@ namespace Discord.API
         public bool Temporary { get; set; }
         [JsonProperty("created_at")]
         public DateTimeOffset CreatedAt { get; set; }
-        [Obsolete("This will always return false. If an invite is revoked, it will not be found and the invite will be null.")]
-        public bool Revoked { get; set; }
     }
 }

src/Discord.Net.Rest/Entities/Invites/RestInviteMetadata.cs

@@ -8,7 +8,8 @@ namespace Discord.Rest
     {
         private long _createdAtTicks;
 
-        [Obsolete("This will always return false. If an invite is revoked, it will not be found and the invite will be null.")]
+        /// <inheritdoc />
+        [Obsolete("This property doesn't exist anymore and shouldn't be used.")]
         public bool IsRevoked { get; private set; }
         /// <inheritdoc />
         public bool IsTemporary { get; private set; }

src/Discord.Net.WebSocket/Entities/Invites/SocketInvite.cs

@@ -48,8 +48,9 @@ namespace Discord.WebSocket
         int? IInvite.PresenceCount => throw new NotImplementedException();
         /// <inheritdoc />
         int? IInvite.MemberCount => throw new NotImplementedException();
-        [Obsolete("This will always return false. If an invite is revoked, it will not be found and the invite will be null.")]
-        bool IInviteMetadata.IsRevoked => false;
+        /// <inheritdoc />
+        [Obsolete("This property doesn't exist anymore and shouldn't be used.")]
+        bool IInviteMetadata.IsRevoked => throw new NotImplementedException();
         /// <inheritdoc />
         public bool IsTemporary { get; private set; }
         /// <inheritdoc />