Issue generated from Tuleap's migration script. Originally submitted by: Emmanuel Lepage Vallee (elv13)

The new time calculation code is broken as each values can be negative and this isn't taken into account.

I will revert to a version based on my old code but including the changes introduced by the rewrite.

It is faster anyway. In my opinion, it is also clear and simple and don't depend on 3rd party APIs at all, just plain C and decimal logic