Pressed to prod

This adds a switch which turns on all paths to use the `pressed.json` files.

This includes all the routes:
 - `/<path>`
 - `/<path>.json`
 - `/collection/<collectionid>`
 - `/collection/<collectionid>/rss`
 - `/collection/<collectionid>.json`

The only thing here is that we are not using the collections endpoint from the content api. This is mainly due to it not being tried and tested yet. Instead we have `getPressedCollection` which figures out what paths a collection exists on, takes the first one, requests the pressed for that path and then extracts out the `Collection` object from it.