SkinLoader: This update introduces a SkinLoader. What this essentially does is load every player head that can potentially appear in the inventory i.e. top fives. This works just fine without this update with the exception of the first time a players head is loaded and displayed. The first time it will show up without a skin until you click the inventory to update it.
The SkinLoader should prevent that pretty consistently.
This has been implemented for both flat file and MySQL, however, a player head is only loaded if they have been on that particular server at least once before.
This has only been tested in online mode. Please let me know if this causes any issues on offline mode servers.