Added the ability to automate any c# scripts for an upgrade process. I realize this is superceded already in 6.0

but we need a way to do this in 4.x too especially for this release since we need to run a script to fix some db
issues. I've added a framework using an UpgradeScriptManager and another install step + unit tests for some of the
UpgradeScriptManager methods.

src/Umbraco.Web/WebBootManager.cs

@@ -9,6 +9,7 @@ using Umbraco.Core.Dictionary;
 using Umbraco.Core.Dynamics;
 using Umbraco.Core.PropertyEditors;
 using Umbraco.Web.Dictionary;
+using Umbraco.Web.Install.UpgradeScripts;
 using Umbraco.Web.Media;
 using Umbraco.Web.Media.ThumbnailProviders;
 using Umbraco.Web.Models;
@@ -90,6 +91,7 @@ namespace Umbraco.Web
             //add the internal types since we don't want to mark these public
             ApplicationEventsResolver.Current.AddType<CacheHelperExtensions.CacheHelperApplicationEventListener>();
             ApplicationEventsResolver.Current.AddType<LegacyScheduledTasks>();
+            ApplicationEventsResolver.Current.AddType<UpgradeScriptRegistrar>();
 
             //now we need to call the initialize methods
             ApplicationEventsResolver.Current.ApplicationEventHandlers