Add support for MAP pricing (hide price outside of the cart)#52

Some manufacturers have “minimum advertised pricing” requirements where storefronts are not allowed to show their pricing on a website unless it’s in the cart.

Shopify actually has some information about this pricing model here as well: https://www.shopify.com/ca/blog/map-pricing

But it doesn’t appear to be something that they’ve added platform support for yet. Perhaps this is something that a specific product template or setting could address.