Use new model for bullet tests
Cant commit without this
Merge branch 'new3dapi' of https://github.com/libgdx/libgdx into new3dapi

Conflicts:
	gdx/src/com/badlogic/gdx/graphics/g3d/Model.java
	gdx/src/com/badlogic/gdx/graphics/g3d/ModelBatch.java
	tests/gdx-tests/src/com/badlogic/gdx/tests/g3d/BatchRenderTest.java
Merge pull request #315 from xoppa/new3dapi

New3dapi