Expand viewport to window size

Pheww... Glad that I figured this out in time.

Replaced multiple attribute pannels with a single uber attribute panel

added lock to scale param

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

Fixes problem of not being able to add children with more than one level of hierarchy.

@sole I hope this solution does the trick for you too ;)

This way the panel illustrates the API better.
It's not too intuitive but eventually the (future) helper will probably make it uneeded.

In the process found some issues:

- HemisphereLight shading is wrong for objects not in origin, it shouldn't depend on light position amplitude and object position in the scene
- GL errors about uniforms thrown when all lights have "visible = false"
- object dragging in the viewport sometimes hits invisible wall (I guess it's because of limited picking plane size?)
- ArrowHelper doesn't seem to work for (0,-1,0) direction

Also fixed spotlights shading in Lambert material and light helpers init colors for light intensities > 1.

Please disregard init scene lighting weirdness, this is just temporary, to be able to test light helpers.

This is for PointLights.

Also removed unused distance property from DirectionalLight class (at least I think so, I know WebGL materials don't use this and I couldn't find it used elsewhere).