Predefined solutions

[pautasso]

Feed a number of solutions into a question so that it can be presented without the asq-exercise and used to discuss solutions.

Original use case: 'js-function-body', collect code answers at the end of a lecture, process answers offline and discuss a selected subset of answers when starting the next lecture. I can make separate slides one per answer so i can correct them using the js-function-body, but it would be nicer to stay in the same slide and use the solution selection to go through them.

[pautasso]

The inject solution now works in the print workflow, but not all question types support solutions.
For example, highlight is perfect, but buckets doesn't seem to allow solutions.