Afterburner

Afterburner 0.2.0. One version number for every build now. What a build contains depends on its Minecraft version.

**Changed**
- Far terrain (where the build has it) starts off: switch it on in Options > Video Settings > Afterburner. Far terrain saved by earlier versions is ignored, and a chunk copied before its light was worked out is no longer saved (that caused gray boxes and black wedges at the horizon).
- Page links, icon, license and third-party notices are in the jar.

**Changed**
- Far terrain pacing on integrated graphics and shadow-map reuse for shader packs (the experimental parts), both included from the 1.21.1 work in progress. This file is a beta because the world-join check of this build was not automated.