Gettin' shit DONE.

-Added Hang Glider model.
-Added Hang Glider render textures.
-Added Unholy tool and weapon textures.
-Added Colored Wooden Door placer item textures.
-Added Glass Door placer item texture.
-Added Potent Bookshelf textures.
-Improved Slime Core texture.
-Improved Ender Core texture.