follow CA1001: Types that own disposable fields should be disposable

https://msdn.microsoft.com/library/ms182172.aspx

shadowsocks-csharp/Controller/Service/AvailabilityStatistics.cs

@@ -16,7 +16,7 @@ namespace Shadowsocks.Controller
 {
     using Statistics = Dictionary<string, List<StatisticsRecord>>;
 
-    public sealed class AvailabilityStatistics
+    public sealed class AvailabilityStatistics : IDisposable
     {
         public const string DateTimePattern = "yyyy-MM-dd HH:mm:ss";
         private const string StatisticsFilesName = "shadowsocks.availability.json";
@@ -342,5 +342,12 @@ namespace Shadowsocks.Controller
                 Server = server;
             }
         }
+
+        public void Dispose()
+        {
+            _recorder.Dispose();
+            _writer.Dispose();
+            _speedMonior.Dispose();
+        }
     }
 }

shadowsocks-csharp/Controller/Strategy/StatisticsStrategy.cs

@@ -12,7 +12,8 @@ using Shadowsocks.Model;
 namespace Shadowsocks.Controller.Strategy
 {
     using Statistics = Dictionary<string, List<StatisticsRecord>>;
-    class StatisticsStrategy : IStrategy
+
+    internal class StatisticsStrategy : IStrategy, IDisposable
     {
         private readonly ShadowsocksController _controller;
         private Server _currentServer;
@@ -152,5 +153,10 @@ namespace Shadowsocks.Controller.Strategy
         {
             //TODO: combine this part of data with ICMP statics
         }
+
+        public void Dispose()
+        {
+            _timer.Dispose();
+        }
     }
 }