v0.7.1

• Breaking change: you must now pass the path to the brush folder upon viewer creation. See examples folder.
• Updated to three v0.139
• GLTF1 Loader which was removed and placed in three-tiltloader, is now back in this package.
• New dependency: three-icosa providing the glTF extension GOOGLE_tilt_brush_material.
• Switched to generic glTF loader with above extension instead - can load a most generic glTF files now!
• Partially animated .tilt files via three-tiltloader