Nostalgia Shader v3.0 Preview E7

Oi, this version got done a bit later than I intended thanks to some stuff keeping me busy but here it is anyways:

* adjusted skylight
* adjusted colorgrading
* adjusted exposure
* adjusted vignette
* added legacy lens flare
* fixed cloud nighttime transition
* clouds are animated using world time by default
* fixed (block) entity rendering with normalmaps on 1.15+
* fixed visual artifacts with impossible surface directions
* added support for the end (WIP)
Also mind the ninja fix for nVidia and nether.