Split the base box into one used for dev and one for the tutorial.

Fixes #509.

TODO:
 1. [ ] Update the documentation. (It will be the same as currently, but for both of the boxes)
 2. [ ] Update the release process to generate a new tutorial image with the just released packages.
It means that the packages (including the dependencies) will already be installed on the box, rather than having to be installed after the machine boots. We could install *just* the dependencies, but then we would need to maintain a list of dependencies here too.