finishes functionality for cart, checkout, return and renter registration

bookish-ui/src/constants/books/action_types.tsx

@@ -4,6 +4,8 @@ const FETCH_BOOKS = generateActionType('FETCH_BOOKS');
 const FETCH_COVER_IMAGE = generateActionType('FETCH_COVER_IMAGE');
 const SET_FILTER = 'SET_FILTER';
 const ADD_TO_CART = 'ADD_TO_CART';
+const REMOVE_FROM_CART = 'REMOVE_FROM_CART';
+const CLEAR_CART = 'CLEAR_CART';
 const CHECKOUT_BOOK = generateActionType('CHECKOUT_BOOK');
 const RETURN_BOOK = generateActionType('RETURN_BOOK');
 
@@ -12,6 +14,8 @@ export const actionTypes = {
     FETCH_COVER_IMAGE,
     SET_FILTER,
     ADD_TO_CART,
+    REMOVE_FROM_CART,
+    CLEAR_CART,
     CHECKOUT_BOOK,
     RETURN_BOOK
 }