Adds IO Helper overload for the views and masterpages

Adds UmbracoSettings to toggle mvc templating support

src/umbraco.businesslogic/IO/IOHelper.cs

@@ -77,7 +77,12 @@ namespace umbraco.IO
 			return Umbraco.Core.IO.IOHelper.ValidateEditPath(filePath, validDir); 
         }
 
-        public static bool ValidateFileExtension(string filePath, List<string> validFileExtensions)
+        public static bool ValidateEditPath(string filePath, string[] validDirs)
+        {
+            return Umbraco.Core.IO.IOHelper.ValidateEditPath(filePath, validDirs);
+        }
+
+	    public static bool ValidateFileExtension(string filePath, List<string> validFileExtensions)
         {
 			return Umbraco.Core.IO.IOHelper.ValidateFileExtension(filePath, validFileExtensions); 
         }

src/umbraco.businesslogic/UmbracoSettings.cs

@@ -546,6 +546,19 @@ namespace umbraco
 			get { return Umbraco.Core.Configuration.UmbracoSettings.ResolveUrlsFromTextString; }
         }
 
+
+        /// <summary>
+        /// Enables MVC, and at the same time disable webform masterpage templates.
+        /// This ensure views are automaticly created instead of masterpages.
+        /// Views are display in the tree instead of masterpages and a MVC template editor
+        /// is used instead of the masterpages editor
+        /// </summary>
+        /// <value><c>true</c> if umbraco defaults to using MVC views for templating, otherwise <c>false</c>.</value>
+        public static bool EnableMvcSupport
+        {
+            get { return Umbraco.Core.Configuration.UmbracoSettings.EnableMvcSupport; }
+        }
+
         /// <summary>
         /// Configuration regarding webservices
         /// </summary>