WebSandboxMC

• Add new blocks: TNT, emerald block, pumpkin, jack-o'-lantern, huge mushrooms, command,
  emerald ore, soul sand, nether brick, soul soil, redstone lamps (satoshinm/NetCraft#157)
• Refactor to lay the groundwork for Sponge support (partial GH-51), not fully implemented but Bukkit should still function as before, if you see any new problems from these changes please let me know

Update to NetCraft build 414:

• Fix wrongly assigned textures for stone brick, log, deadbush, jukebox, and orange wool (satoshinm/NetCraft#155)
• Improve the build info line text (satoshinm/NetCraft#156)