Further progress towards tenant-specific routing

Ability to follow redirects from integration tests
Route publisher wraps handler with ShellRoute which controls request lifetime scope
ShellRoute at the moment is restricted to "Default" - host and prefix TBD
Route publisher remove-and-insert routes for a specific tenant to allow incremental and repeated shell route publish
Offers a more deterministic knowledge of which shell container is used than just-in-time http context
Removes Autofac default httpmodule, controller factory, httpapplication icontainerprovideraccessor, etc
Adds support for optional ~/Config/Sites.{yourtenantname}.config file for manual per-shell component override
Integration tests capture Orchard and NHibernate trace output. Levels are configurable in orchard.specs diagnostics.config
Concept of IRunningShellTable instroduced. Might not be needed - will be removed if so.

--HG--
branch : dev

src/Orchard.Web/Modules/Orchard.MultiTenancy/Controllers/AdminController.cs

@@ -33,10 +33,8 @@ namespace Orchard.MultiTenancy.Controllers {
         }
 
         [HttpPost, ActionName("Add")]
-        public ActionResult AddPOST() {
-            var viewModel = new TenantsAddViewModel();
+        public ActionResult AddPOST(TenantsAddViewModel viewModel) {
             try {
-                UpdateModel(viewModel);
                 if (!Services.Authorizer.Authorize(Permissions.ManageTenants, T("Couldn't create tenant")))
                     return new HttpUnauthorizedResult();
                 _tenantService.CreateTenant(