dev-haskell/constraints: bump up to 0.3.4.2

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
dev-haskell/hexpat: bump up to 0.20.4

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
dev-haskell/diagrams-svg: bump up to 0.8.0.2

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>