Documented lhs options in man page and README.
Note: HTML output with --lhs-out is not strictly literate haskell,
but it is designed so that the result of copying and pasting the
page in the browser will be a literate haskell file.
git-svn-id: https://pandoc.googlecode.com/svn/trunk@1501 788f1e2b-df1e-0410-8736-df70ead52e1b