MeshPhysicalMaterial: added transparency

AnimationLoader: Inherit from Loader.

TS: add more fromArray and toArray function types

OBJLoader2 V3.0.0

AudioLoader: Inherit from Loader.

Matching js material class names with glsl defines

Vector2/3/4: add toArray and fromArray function types with array-likes

Fix issue in shadow map refactor

- OBJLoader2: It now extends OBJLoader2Parser: Moved common functions (parser configuration and callback) to OBJLoader2Parser
- OBJLoader2Parser: All private functions are now identified by "_".
- Aligned typescript definitions with latest code changes and updated code documentation where needed.
- Polished code
- Set versions to 3.0.0

Material: Added .toneMapped property

Separated the meanings of PHYSICAL

Loader: Introduce new API.

Fix DefaultMatrixAutoUpdate type in docs

Shadow cleanup and refactor

TS: Clean up LoadingManager.

Loaders: Remove obsolete callbacks.