Removed PdfViewController, HtmlViewRenderer and FakeView to be replaced with ViewEngineResult Render method

Added HttpException class for missing HttpException for net8

Wrapped HttpContext.Session, GetJsonResult, IsAjaxRequest and GetUserIdentityName in controllers for net8

Added AuthenticationService to test Fab2ApprovalMKLink code for net8

Compile conditionally flags to debug in dotnet core

Fab2ApprovalSystem/Misc/SessionExpireFilterAttribute.cs

@@ -4,7 +4,9 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Web;
+#if !NET8
 using System.Web.Mvc;
+#endif
 
 namespace Fab2ApprovalSystem.Misc {
 
@@ -16,7 +18,7 @@ namespace Fab2ApprovalSystem.Misc {
 
             // check if session is supported
 
-            if (session[GlobalVars.SESSION_USERNAME] == null) {
+            if (GlobalVars.IsUserNameNull(session)) {
                 // check if a new session id was generated
 
                 // this will force MVC to use the standard login redirect, enabling ReturnURL functionality