create a sim with multiple screens

[pixelzoom]

It would be nice if simula-rasa was capable of generating a sim with multiple screens. It currently generates a single-screen sim, and then you have to manually set up any additional screens (typically via repetitive copy-paste).

Adding a --screens options would be nice, something like this:

grunt create-sim --repo=natural-selection --author=me --title="Natural Selection" --screens="Intro, Lab"

Looks like a nontrivial amount of work to do this. It would be nice to have, but not essential. Low priority.