More pernament solution for ee99320120c8de15f24fc4d0af5262e224b9ccc3

This method to include files in a jar is also used by Sponge:
https://github.com/SpongePowered/Sponge/blob/0f2ad25d854ec46af6bdfbd3e1dffae09176c34d/build.gradle#L81
Abstract the byte array in chunk generation away

Minecraft 1.8 doesn't pass around raw arrays anymore. Even in Minecraft
1.7 we needed to rewrite our arrays for Minecraft's format. This can be
made more efficient by introducing a ChunkBuffer interface, that
immediately writes to the preferred format for Bukkit/Forge.

The Forge implementation of ChunkBuffer now supports block data.
However, the Bukkit implementation does not. (Bukkit API limitation.)
For consistency, the config files still strip out block data
informatation from the Surface/Ground/StoneBlock settings. Once we
upgrade to Minecraft 1.8 the Bukkit implementation will be gone, and we
can remove this limitation from the config files.

However, any performance improvement is negated by the fact that we now
create lots of LocalMaterialData instances. Every time a material needs
to be checked a new one is created, which happens around 1000 times for
each chunk. (surface blocks, caves, canyons) The next commit will fix
this.
Add a cache for LocalMaterialData objects

The amount of objects could easily exceed 50000 previously, as they were
created for every block lookup, even during chunk generation. Now they
are cached in an IdentityHashmap, using Minecraft's Block class as the
key.
Replace some calls with DefaultMaterial.AIR

In a0c90789d12092ed9c84a9bc16173d468f481b7c a method was added that
makes checking for air a little faster. It saves exactly one lookup call
to a HashMap (the one to convert DefaultMaterial into a Minecraft
Block). That tiny difference mattered a lot for performance critical
things like chunk generation, where checking for air happens *a lot*.

For consistency all calls in terrain population were changed too. It
doens't give a measurable performance benefit.

Again just for consistency a call in BukkitWorld was changed to mirror
the call in BukkitChunkBuffer (and ForgeWorld and ForgeChunkBuffer).