Refactor entity setup.

[StarArawn]

Currently the map entity just loads the mesh and the spawns a bunch of chunk entities. Instead we should think about having the map entity stick around and contain a transform for moving the entire map around. The chunk entities can be children of the map entity.

[wmiller848]

Utilizing the parent relationship would be ideal. Adjusting a single transform on the parent entity instead of each of the the chunks would be nice.