refactor phoenix rendering

[ruby0x1]

So, since the new luxe won't be compatible (see dev log #1), there are some new options available to improve phoenix in time.

I'm not sure how this will look - but merges will be done incrementally.
There is no expected timeline for this, finishing 1.0 is my priority, the old code base is being used in some projects that will benefit from these improvements. See the dev logs for in depth details of the scope of changes coming to luxe itself.

Changes will be done in branches and PR'ed into master so they are easy to follow.
It's also important not to try to jump into volatile changes too early, I will make a proper status post when significant benefits are available to existing projects.

I'll also add notes here as I go along.

• Renderer shouldn't be tied to Batcher type
• Renderable interface (volatile)
• Per geometry blend mode
• Bring in new maths classes? (lot's of renaming functions for consistency)