Add Coq 8.4_p2.
Update manifest of Asus drivers.
Add xorg-server with nvidia autoconfig patch.
Remove disper 0.3.0.
Remove i3.
Add proof general 4.2 ebuild.
Add mtac keyword to coq ebuild.
Add ssreflect ebuild.
Add containters library for Coq.
Remove biber; use cschwan's overlay instead.