Initial tests usually dont provide much value... but they save us

later in the game!

Signed-off-by: Rachel Thompson <r.thompson@modcloth.com>
Charges  per book

Signed-off-by: Adam Kalnas <a.kalnas@modcloth.com>
Charges 6 for two copies of the same book.

Signed-off-by: Adam Kalnas <a.kalnas@modcloth.com>
Discounts book bundles for groups of 2 books

Signed-off-by: Adam Kalnas <a.kalnas@modcloth.com>
Discounts for other book bundles

Signed-off-by: Adam Kalnas <a.kalnas@modcloth.com>