Display meals already bought for multiple children

[saraguirgis]

• DONE - Write function to show all items ordered matching sku or ID, and return array with "Purchased for [getChildShortDisplayName]" for each child it was purchased for

Helpful link: https://stackoverflow.com/questions/38769888/check-if-a-customer-has-purchased-a-specific-products-in-woocommerce

Clean up:

• DONE - Comment out the code that makes the calendar view display "View Details" instead of "order" if the product was previously purchased
• DONE - Comment out the code that removes the add to cart button if the product was previously purchased