Merge remote-tracking branch 'origin/netcore/dev' into netcore/bugfix/logging-fixing

# Conflicts:
#	src/Umbraco.Tests.Integration/RuntimeTests.cs
#	src/Umbraco.Tests.Integration/Testing/UmbracoIntegrationTest.cs
#	src/Umbraco.Web.Common/Extensions/UmbracoCoreServiceCollectionExtensions.cs

src/Umbraco.Web.UI.NetCore/Startup.cs

@@ -76,6 +76,7 @@ namespace Umbraco.Web.UI.BackOffice
             {
                 app.UseDeveloperExceptionPage();
             }
+            app.UseStatusCodePages();
             app.UseUmbracoCore();
             app.UseUmbracoRequestLogging();
             app.UseUmbracoWebsite();