Still not done.

No markup learning, no compilation process. Just simple HTML.
Still, working on it.

Added Vector3.absoluteToRelative and Vector3.relativeToAbsolute. Thanks to @G3z for the initial suggestion. Thanks to @em for the naming hint. Fixes #1043.

Inverse mask effect stopped working as it depended on buggy stencil buffer being always turned on due to spelling error (which got fixed recently).

Matrix4.lookAt(): y doesn't need to be normalized because it's a cross product of 2 normalized vectors

Not sure it's really correct, it's kinda hard to tell.

Also made stress test more fancy and heavy. It's interesting how antialiasing increases performance difference for more complex materials.

Also some shaders refactoring.

Still todo: doubleSided handling for reflections / refractions.

As per discussion in #1324

This fixes geometry tessellation example (before TextGeometry by default was having UVs defined for just a subset of faces).

Fixed: The DOMRenderer was not using the correct members from the result of the projectScene() function, which ended up meaning that no DOM elements were being updated at all.