fix(Physgun): Rotation works now.
I think i took it from SourceBox or whatever it was called.
feat(Portal 2): I don't remember what i did but i did something.
A lot of that something was taken from:
https://github.com/RocketLauncher21/Portal2ASW
chore(ImGui): Updated ImGui to latest.
chore(Polyhedron): Changed a lot i don't remember where i took it from.
refactor(env_projectedtexture)!: Updated to the KS:GO version,
still doesn't support anything because of `materialsystem`.
refactor(fog_controller): Updated to the KS:GO version.
chore(CBaseEntity): Remove the "Updating physics on object in hierarchy"
warning.
