Dynmap Bukkit for 1.11

Dec 2 EDIT: Partially fixed rotations for shulker bottoms and added full support for 1.9 command blocks

For the DynmapCore 1.11 pull request, see webbukkit#74

These are builds of Dynmap-Bukkit, DynmapCore and DynmapCoreAPI that:

• Implements rendering of missing 1.9 blocks: beetroot, repeating & chain command blocks, frosted ice, end gateway
• Implements rendering of 1.10 blocks: magma, nether wart block, red nether brick, bone blocks, structure blocks
• Implements rendering of 1.11 blocks: observers, all shulker box colors
• Adds support for ShulkerTextureFile (shulker box maps)
• Adds the end sky texture; makes end portals and gateways render using that, instead of obsidian