Merge branch 'wip/romes/migration-v2' into 'master'

ci/config.cabal.project

ci/default.nix

patches/Agda-2.6.3.patch

patches/configuration-tools-0.7.0.patch

patches/darcs-2.16.5.patch

patches/entropy-0.4.1.10.patch

patches/executable-hash-0.2.0.4.patch

patches/ghc-paths-0.1.0.12.patch

patches/gi-glib-2.0.29.patch

patches/gi-gobject-2.0.30.patch

patches/haskell-gi-0.26.7.patch

patches/hlibgit2-0.18.0.16.patch

patches/mysql-0.2.1.patch

patches/nix-paths-1.0.1.patch

patches/postgresql-libpq-0.10.0.0.patch

patches/singletons-base-3.2.patch

patches/stack-2.13.1.patch