Problem multiple output nodes

[jajoe]

There are problems when we have many output nodes. As you can see in the tests, one of them is skipped because it's not possible to find the good result for a problem where we need many output node (test 'Big test case 2').

Our source of inspiration has the same problem, as you can see in this Gist.

So currently, we have no solutions for problems with multiple output nodes...