Use dev version of doclayout.

Author: jgm

cabal.project

@@ -11,3 +11,8 @@ source-repository-package
   type: git
   location: https://github.com/jgm/texmath
   tag: 85d7c9aaa19c9cc5f53f1cd56384cf89bef83ca4
+
+source-repository-package
+  type: git
+  location: https://github.com/jgm/doclayout
+  tag: af6563972de73ead9f37de44ccca1c86b09a7cec

stack.yaml

@@ -20,6 +20,8 @@ extra-deps:
 - zip-archive-0.4.3.1
 - git: https://github.com/jgm/texmath
   commit: 85d7c9aaa19c9cc5f53f1cd56384cf89bef83ca4
+- git: https://github.com/jgm/doclayout
+  commit: af6563972de73ead9f37de44ccca1c86b09a7cec
 
 ghc-options:
    "$locals": -fhide-source-paths -Wno-missing-home-modules