Merge pull request #578 from fumieval/master

Add several packages I maintain

build-constraints.yaml

@@ -975,6 +975,13 @@ packages:
     "Athan Clark <athan.clark@gmail.com> @athanclark":
         - nested-routes
 
+    "Fumiaki Kinoshita <fumiexcel@gmail.com> @fumieval":
+        - control-bool
+        - monad-skeleton
+        - objective
+        - witherable
+        - xml-lens
+
     "Stackage upper bounds":
         # https://github.com/fpco/stackage/issues/476
         - vector-space < 0.10