Raytracer

This is the final version of the original raytracer with BVH implemented.
The project is now moved onto path tracing.

First user usable release

Edit Scene.xml and run the exe to render it with the ray tracer.
Example.xml attached shows what you can do, control and add lights, planes, spheres and the camera.
Add as many spheres/planes and lights as you want in any order. Define only one camera.

Inside each xml element, please keep the order of attributes and child elements. If this is not respected, unexpected behaivour can occur.