Make fail_recovery tests default

[AbyelT]

The tests in recovery_test.rs are currently ignored, the reason is that they do not correctly answer the futures of the last proposals.

The futures are stored as a LinkedList and handled in the answer_future() function, currently it reads decided entries and replies to futures in a random order. It would be better to check and reply to the future each decided entry matches to.

By using Ask<Value, ()>, one could include the proposals in the Futures and check the futures that should be replied to.