Changelog for feed-0.3.9.2

Version 0.3.9.1: * add ref to github repo + .cabal tidying. Version 0.3.9: * tidy up compilation with ghc-7.6(.3), bumped version (but no functional changes.) Version 0.3.8: * cabal build fixes. Version 0.3.7: * <feed> parsing: made <title> be optional. * <entry> parsing: try <published> if <updated> is missing.