Support W3C incoming headers in opt-in mode

CHANGELOG.md

@@ -1,5 +1,8 @@
 # Changelog
 
+## Version 2.5.0-beta1
+- [Adds opt-in support for W3C distributed tracing standard](https://github.com/Microsoft/ApplicationInsights-aspnetcore/pull/735)
+
 ## Version 2.4.1
 - Patch release to update Web/Base SDK version dependency to 2.7.2 which fixed a bug (https://github.com/Microsoft/ApplicationInsights-dotnet-server/issues/970)
 

src/Microsoft.ApplicationInsights.AspNetCore/DiagnosticListeners/Implementation/HeadersUtilities.cs

@@ -1,10 +1,10 @@
 namespace Microsoft.ApplicationInsights.AspNetCore.DiagnosticListeners
 {
-    using Microsoft.ApplicationInsights.AspNetCore.Common;
     using System.Collections.Generic;
     using System.Globalization;
     using System.Linq;
     using System.Text.RegularExpressions;
+    using Microsoft.ApplicationInsights.Common;
 
     /// <summary>
     /// Generic functions that can be used to get and set Http headers.