Material: Clean up usage of .lights property.

Material: Move .lights property to ShaderMaterial.

NodeMaterial - Fix DoubleSided and BackSided NormalMap flipped

Update WebGLRenderer.d.ts

Fixes a typo where the `WebGLRendererParameters` exposes `pixelRation` rather than `pixelRatio`.

Remove dup paragraph in disposing objects doc

I deleted a duplicate paragraph from the "How to dispose of objects" page in the docs.

Fix ShapeUtils typing

Holes are essentially an array of contours. This means they should be Vec2[][] instead of Vec2[].

Function has already been removed from the codebase and is not part of the public API.

WebXRManager: Clean up.

TS: Clean up.

Examples: Clean up.

VRMLLoader: Make normal computation more robuste.

Vector3: Improve feedback of .angleTo().

All Texture values in Material type definitions are now nullable.

This reverts commit 0b621c65.

WebGLProgram: Refactored multiview code.

NormalMap Shader: prevent branching

This reverts commit cfb584d9.

WebGLMultiview: Brought back non-ArrayCamera code path and only use in VR.