refs https://github.com/TryGhost/Team/issues/1079
These were missing when benefits were added to products, and will allow
theme developers to make more useful custom subscribe pages.
refs https://github.com/TryGhost/Team/issues/1252
In order to allow existing subscribe pages to continue working without
an extra flag, we're going to filter out the archived tiers.
Since we now have 2 products by default for all ghost sites, free and default paid, the usage of default product which so far was using first product needs to be updated to use the first paid product.
- updates default product usage to use first paid tier
- updates tests
- one big file full of stuff is never good for clarity
- separating it out helps us see what requires what
- it also highlights the awful naming and opaque behaviour we have in themes - much to do, but this helps us start
