Added two new web components for the cart page:
- product-tile
- cart-page-item
Utilized the sections API for pulling updated content.
Added a new section for the upsells, with a block for adding the upsell required product, and the product to display in the upsells if the required product is in the cart (will also not display the upsell if it is also in the cart).
NOTE: I left out upsells set in the cart template by default since there's probably differences in test products between stores.