[CONTENT] Add adventure with only visible output screens.

[MarleenGilsing]

I would like to add adventures that have a hidden inputcode, but you can still run it and see the output. The student has to recreate the code.
This could also be done in a quiz form, so the students get like 5 codes increasing in difficulty to recreate.

I could make this, don't know how yet, but I'll make it an issue so I don;t forget about it.

[Felienne]

Is this the same as (or similar to) #1936 but more generic?

[MarleenGilsing]

If this issue is possible, we wouldn't need #1936, because we could show the end result of any code, so turtle code too.
If this issue is (too) hard to create, then #1936 would be a nice shortcut, because I could just make some screenshots of turtledrawings and place them in the adventure as an image. But of course it would be nicer if the turtle moved instead of just a screenshot.