added editor class and few methods

removed uuid

Implemented more methods

editor refactoring

editor refactoring

editor api improvements

finished editor API

hooked up editor to UI as an argument

Not sure if helpers should be fogged or not. It does look pretty weird when they are not fogged. Also having helpers fogged helps to get a sense of the fog effect over larger space.

Maybe there could be a checkbox for enabling this, to be able to see things if they need to be modified while in the fog.

Also found and fixed a bug deep in WebGLRenderer, where shaders were not recompiled when changing fog types because fog type wasn't taken into account when creating shader code hash. Phew, that was a tough one to figure out. This Editor thingie really forces us to dust all nooks and cranies of the codebase ;)

This buggy pattern ("something = parameter || nonzero value") exists at more places though elsewhere setting to zero doesn't make that much sense (e.g. in geometries).

Not sure if we should change it everywhere to proper pattern ("something = ( parameter !== undefined ) ? parameter : value").

Maybe it would be good for establishing habit. I remember fixing this buggy pattern long ago but it just keeps popping up.

For the moment, it works just on Basic / Lambert / Phong materials.

Fog must be added to the scene before initialization of WebGLRenderer and scene must be passed to WebGLRenderer constructor (like for lights).

I don't know yet how to solve properly MeshShaderMaterial & co :(

Starting to prepare stuff for adding Fog. Having Fog.js inside /scenes doesn't sound right, but I guess it can be there for now...
The idea would be to do `scene.fog = new THREE.Fog( color, near, far );` This way seems consistent with the rest of the API. By default `scene.fog` is `null`.