Add noDuplicates on Property

[dubzzz]

Handle the case where generator cannot return unseen values anymore

[dubzzz]

Instead of adding a noDuplicates feature, the idea is to remove the unnecessary zero values produced by the fc.integer() shrink.

Basically if the failing range is [1, 20] and it failed first at 18, it will try the following values:
0, 9, 0, 5, 0, 3, 0, 2, 0, 1

The idea is too keep this fast convergence towards zero but do not shrink to it after:
0, 9, 5, 3, 2, 1

It solves partially the issue as values can still be duplicated but the fix is far less intruisive and better in terms of performances and reliability.