[Ryzom Game Functionality] Implement Character Achievements

by SirCotare for WorldForge

When achievements for Ryzom were introduced on the Ryzom Armory[1], the resonance from the community was very good. I'd like to give every player the chance to benefit from achievements without relying on third-party mechanisms. Therefore the current achievement system should be moved onto the Ryzom servers, allowing for a more detailed progress tracking and also access to the achievements via WebIG.