Update spinehaxe for new Spine features

I try to upgrade Spine library for new features in java runtime. It's only first step and very fast and dirty. 
Also i try to add some tests in project. I find some bugs in TextureAtlas (for ex. if atlas has size entity, project will crash), but don't improve it yet. 

In my mind, if I create pull request now, it's more simple to merge if I rewrite more codes in project.