modofiy class access level for diagnostics.

src/DotNetCore.CAP/Internal/ConsumerContext.cs

@@ -8,7 +8,7 @@ namespace DotNetCore.CAP.Internal
     /// <summary>
     /// A context for consumers, it used to be provider wrapper of method description and received message.
     /// </summary>
-    internal class ConsumerContext
+    public class ConsumerContext
     {
         /// <summary>
         /// create a new instance of  <see cref="ConsumerContext" /> .

src/DotNetCore.CAP/Internal/ConsumerExecutorDescriptor.cs

@@ -9,7 +9,7 @@ namespace DotNetCore.CAP.Internal
     /// <summary>
     /// A descriptor of user definition method.
     /// </summary>
-    internal class ConsumerExecutorDescriptor
+    public class ConsumerExecutorDescriptor
     {
         public MethodInfo MethodInfo { get; set; }