Make sure to collect distinct faults

[protopyte]

I would expect fault collection to also monitor that they are different from each other. I didn't see any other way than tracking which fault belonged to which group, let me know if you have something simpler in mind. I could go a step further and kill encstatus/decstatus, relying on the length of the sets.

[protopyte]

Second version of the patch, avoiding the management of the per group sets at the expense of a search in the known faults

[doegox]

thanks!