Fixed exception in model binding, causing event settings to never be persisted.

src/Orchard.Web/Modules/Orchard.AuditTrail/Drivers/AuditTrailSettingsPartDriver.cs

@@ -42,11 +42,11 @@ namespace Orchard.AuditTrail.Drivers {
                     select new AuditTrailCategorySettingsViewModel {
                         Category = categoryDescriptor.Category,
                         Name = categoryDescriptor.Name,
-                        Events = eventsQuery.ToArray()
+                        Events = eventsQuery.ToList()
                     };
 
                 var viewModel = new AuditTrailSettingsViewModel {
-                    Categories = categoriesQuery.ToArray() 
+                    Categories = categoriesQuery.ToList() 
                 };
 
                 if (updater != null) {

src/Orchard.Web/Modules/Orchard.AuditTrail/ViewModels/AuditTrailCategorySettingsViewModel.cs

@@ -5,6 +5,6 @@ namespace Orchard.AuditTrail.ViewModels {
     public class AuditTrailCategorySettingsViewModel {
         public string Category { get; set; }
         public LocalizedString Name { get; set; }
-        public IEnumerable<AuditTrailEventSettingsViewModel> Events { get; set; }
+        public IList<AuditTrailEventSettingsViewModel> Events { get; set; }
     }
 }