Add ContactsController and sorting by name
Add onSale function property to filter products with isOnSale as true
true is default for filterBy, removed since it's default
Add slice to filterBy to return only first 3 products with isOnSale: true
Update index template to loop through onSale filter function
Update Product fixtures for more detailed descriptions
Watching for changes on Product.isOnSale property; Update ProductIndexRoute to use Product model