ShaderMaterial: Fixed copy of defines.

Fix link to materials skin example

Examples: Clean up

Docs: Added SVGRenderer page.

Added basic functionality to SVGLoader.

Docs: Clarified Raycaster.intersectObject().

GearVRController: Added Oculus Go support.

WebGLState minor clean up

Mesh: Remove redundant property .index in .raycast()

GLTFLoader: Clean up extensions example.

Removed webgl_lines_cubes.html

Flatten UUID strings with .toUpperCase() to save heap memory space.

Replace GLTF2Loader with GLTFExporter in BrowserSupport doc

Change variable name from cube to klein

Because the object is not a cube, it's a klein bottle.