Annotate your modules with Haddock headers

[tomtau]

This is a task for everyone, so do it and reassign this task to the person below you alphabetically.
https://wiki.haskell.org/Programming_guidelines#File_Format

#!haskell
{- |
Module      :  <File name or $Header$ to be replaced automatically>
Description :  <optional short text displayed on contents page>
Copyright   :  (c) 2014-2015 HKU
License     :  BSD3

Maintainer  :  <email>
Stability   :  unstable | experimental | provisional | stable | frozen
Portability :  portable | non-portable (<reason>)

<module description starting at first column>
-}