Update OcelotLogger to accept name of class

OcelotLogger now has a property called "Name" intended to store the name
of the type for which the logger has been built for. This is intended to
keep the code a little bit cleaner and also allows for a few extention
methods for common logging scenarios

src/Ocelot/Logging/AspDotNetLogger.cs

@@ -9,8 +9,11 @@ namespace Ocelot.Logging
         private readonly ILogger _logger;
         private readonly IRequestScopedDataRepository _scopedDataRepository;
 
-        public AspDotNetLogger(ILogger logger, IRequestScopedDataRepository scopedDataRepository)
+        public string Name { get; }
+
+        public AspDotNetLogger(ILogger logger, IRequestScopedDataRepository scopedDataRepository, string typeName)
         {
+            Name = typeName;
             _logger = logger;
             _scopedDataRepository = scopedDataRepository;
         }

src/Ocelot/Logging/AspDotNetLoggerFactory.cs

@@ -17,7 +17,7 @@ namespace Ocelot.Logging
         public IOcelotLogger CreateLogger<T>()
         {
             var logger = _loggerFactory.CreateLogger<T>();
-            return new AspDotNetLogger(logger, _scopedDataRepository);
+            return new AspDotNetLogger(logger, _scopedDataRepository, typeof(T).Name);
         }
     }
 }

src/Ocelot/Logging/IOcelotLoggerFactory.cs

@@ -15,5 +15,10 @@ namespace Ocelot.Logging
         void LogDebug(string message, params object[] args);
         void LogError(string message, Exception exception);
         void LogError(string message, params object[] args);
+
+        /// <summary>
+        /// The name of the type the logger has been built for.
+        /// </summary>
+        string Name { get; }
     }
 }

src/Ocelot/Logging/OcelotLoggerExtensions.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Ocelot.Logging
+{
+    public static class OcelotLoggerExtensions
+    {
+        public static void TraceMiddlewareEntry(this IOcelotLogger logger)
+        {
+            logger.LogTrace($"entered {logger.Name}");
+        }
+
+        public static void TraceInvokeNext(this IOcelotLogger logger)
+        {
+            logger.LogTrace($"invoking next middleware from {logger.Name}");
+        }
+
+        public static void TraceInvokeNextCompleted(this IOcelotLogger logger)
+        {
+            logger.LogTrace($"returned to {logger.Name} after next middleware completed");
+        }
+
+        public static void TraceMiddlewareCompleted(this IOcelotLogger logger)
+        {
+            logger.LogTrace($"completed {logger.Name}");
+        }
+    }
+}