Rewritten using codes from recently updated OfflineSkins.
You need Java 8 now, Java 7 won't load.
Relicensed under MIT License.
Providers using Crafatar have been updated to use uuid only.
Added support for using custom skin server.
Added support for HD skins. (you will need to use custom skin server to host your HD skins)
Added support for vanilla PlayerHeads to display properly.
Added partial support for Headcrumbs. (this simply removes Headcrumbs' vanilla TileEntitySkullRenderer override)