Scalable Jets and fix depthTest

[9inpachi]

Closes #103

Hi,

Description

This makes the Jets scalable and also allows to extend UI menu options for each object type which can be used with any loader (by using the PhoenixLoader.addObjectType method from a child class).

I have been trying out options to scale Jets since yesterday but removing and recreating the Jets with increased energy wasn't working for large number of Jets. So after a lot of tries I came up with a minimal method which I think is the best.

Added

• Fixed depthTest not working correctly
• Removed custom synchronous function to loop through children for changing depthTest (I am not sure why but Object3D.traverse seems to work now - while depthTest only worked with updateChildrenDepthTest function earlier)
• Made Jets scalable by increasing their scale and changing their position
• Ability to scale Jets from 1% to 200%
• Increased maximum Jet length to 3000 as it looks like a better option
• Mechanism to add exclusive options to each event data type folder of dat.GUI through an optional callback passed to PhoenixLoader.addObjectType

Screen Capture

[EdwardMoyse]

Fine for now, but I think this is something we should make configurable (the appropriate maximum length will depend a lot on the experiment)

[9inpachi]

I agree. May be we can apply some sort of normalization.

It's also possible to check this directly in the loaders and change the energies from there.