Fixes: U4-2577 Can't save umbraco user - without re-filling in the password

Fixes: U4-541 Wrong dictionary key when using in backend template names
This changes the way that the value that is stored in the auth cookie. Previously we just stored a GUID which was the user's contextid stored in the db, now we store encrypted values of a few necessary user objects. In 6.2 we'll actually set a real .Net user object on the HttpContext. For now, the http module will simply just ensure that the culture is set correctly for the currently logged in user.

src/Umbraco.Web/UI/Pages/UmbracoEnsuredPage.cs

@@ -51,14 +51,6 @@ namespace Umbraco.Web.UI.Pages
                     Response.Redirect(SystemDirectories.Umbraco + "/logout.aspx?redir=" + Server.UrlEncode(Request.RawUrl), true);
             }
         }
-       
-        protected override void OnInit(EventArgs e)
-        {
-            base.OnInit(e);
-
-            System.Threading.Thread.CurrentThread.CurrentCulture = new System.Globalization.CultureInfo(ui.Culture(Security.CurrentUser));
-            System.Threading.Thread.CurrentThread.CurrentUICulture = System.Threading.Thread.CurrentThread.CurrentCulture;
-        }
 
         /// <summary>
         /// Gets/sets the app that this page is assigned to