Hi Guixers,

Here's a patch to add Godot 4! I've tested it builds and can load some sophisticated examples, working with the new Vulkan support. There is no longer a headless build so that has been removed as an output. The previous version, godot@3 is an LTS release now (and in need of an update I see) so I kept that as godot-lts.

I wasn't sure how best to break this up in commits, let me know if these should be separate and how (1. rename godot to godot-lts and 2. add godot@4?). I did my best to put in all the changes in the package definition from 3 to 4 in the changelog, but please do check. Due to the amount and scope of changes I didn't think godot-lts could easily inherit from godot.

Thanks!
John