Add <remarks> tag to the IGuildIntegration xmldocs

src/Discord.Net.Core/Entities/Guilds/IGuildIntegration.cs

@@ -18,6 +18,12 @@ namespace Discord
         bool IsEnabled { get; }
         /// <summary> Gets if this integration is syncing or not. </summary>
         /// <returns> A value indicating if this integration is syncing. </returns>
+        /// <remarks>
+        ///     An integration with syncing enabled will update it's "subscribers" on
+        ///     an interval, while one with syncing disabled will not.
+        ///     A user must manually choose when sync the integration
+        ///     if syncing is disabled.
+        /// </remarks>
         bool IsSyncing { get; }
         /// <summary> Gets the ID that this integration uses for "subscribers". </summary>
         ulong ExpireBehavior { get; }