[Rendering] Move Deferred lighting to a singular pass instead of a bunch of mesh drawers

[michaelsakharov]

Things like Point/Spot lights could remain as mesh's since we can utilize GPU instancing for a reasonably large number of lights without having to add in tiled lighting or anything too fancy.

So just Ambient lighting and DIrectional lighting could all be merged into 1 pass instead of 1 pass for each light in the world.