Refactoring.

Source/MQTTnet/Server/IMqttServer.cs

@@ -19,8 +19,8 @@ namespace MQTTnet.Server
         Task<IList<IMqttClientStatus>> GetClientStatusAsync();
         Task<IList<IMqttSessionStatus>> GetSessionStatusAsync();
 
-        Task<IList<MqttApplicationMessage>> GetRetainedMessagesAsync();
-        Task ClearRetainedMessagesAsync();
+        Task<IList<MqttApplicationMessage>> GetRetainedApplicationMessagesAsync();
+        Task ClearRetainedApplicationMessagesAsync();
 
         Task SubscribeAsync(string clientId, ICollection<TopicFilter> topicFilters);
         Task UnsubscribeAsync(string clientId, ICollection<string> topicFilters);

Source/MQTTnet/Server/MqttServer.cs

@@ -77,7 +77,7 @@ namespace MQTTnet.Server
             return _clientSessionsManager.GetSessionStatusAsync();
         }
 
-        public Task<IList<MqttApplicationMessage>> GetRetainedMessagesAsync()
+        public Task<IList<MqttApplicationMessage>> GetRetainedApplicationMessagesAsync()
         {
             return _retainedMessagesManager.GetMessagesAsync();
         }
@@ -179,7 +179,7 @@ namespace MQTTnet.Server
             }
         }
 
-        public Task ClearRetainedMessagesAsync()
+        public Task ClearRetainedApplicationMessagesAsync()
         {
             return _retainedMessagesManager?.ClearMessagesAsync();
         }

Source/MQTTnet/Server/Status/IMqttSessionStatus.cs

@@ -6,8 +6,6 @@ namespace MQTTnet.Server.Status
     {
         string ClientId { get; set; }
 
-        bool IsConnected { get; }
-
         long PendingApplicationMessagesCount { get; set; }
 
         Task ClearPendingApplicationMessagesAsync();

Source/MQTTnet/Server/Status/MqttSessionStatus.cs

@@ -17,8 +17,6 @@ namespace MQTTnet.Server.Status
         public string ClientId { get; set; }
 
         public long PendingApplicationMessagesCount { get; set; }
-
-        public bool IsConnected { get; set; }
     
         public DateTime CreatedTimestamp { get; set; }