Update Forge to 10.12.0.1012. Merged latest 1.6.4 patches.

Applied Spigot patch
https://github.com/SpigotMC/Spigot/blob/master/CraftBukkit-Patches/0098-Reduce-memory-of-hiddenPlayers-map.patch
[Bleeding] Fix Achievements and Statistics API. Fixes BUKKIT-5305

Applied patch Bukkit/CraftBukkit@80e069d9d556e59771f6a7d0fb6050dcf6c86f06
Merge pull request #1 from MinecraftPortCentral/master

Grab commits from Master