* Simplified code a lot, bias based on normalized cascade size.
* Lets scale cascades, max distance, etc. without creating acne.
* Fixed normal biasing in directional shadows.
I removed normal biasing in both omni and spot shadows, since the technique can't be easily implemented there.
Will need to be replaced by something else.
The Optimized shadow depth range was removed in late 2020 in favor
of the Stable shadow depth range, but it still had a (broken) property
that allowed to enable it.
