Add first compo

src/Dodge/Layout/Tree.hs

@@ -1,9 +1,12 @@
+{-|
+Combining and composing trees.
+-}
 module Dodge.Layout.Tree
     where
 import Data.Tree
 import Control.Monad.State
 import System.Random
--- Left elements get new children, Right elements inherit the children from the
+-- | 'Left' elements get new children, 'Right' elements inherit the children from the
 -- mapped over node
 expandTreeBy :: (a -> Tree (Either b b)) -> Tree a -> Tree b
 expandTreeBy f (Node x []) = fmap removeEither (f x)