Release 0.4.2

[Jürgen Nicklisch-Franken]

This release has changes in the session format. Throw away your
old .session files.


  * Renamed usages pane to references (refs). Added scope to references
  * Command line option to extract cabal-install tars
  * fixed "first start" bug
  * import helper with ghc parser. Try this out!
  * fixed new module bug
  * Get rid of New. for gtk modelview
  * remember tree expansion in modules pane
  * text search takes current selection
  * changed "enter" key for text search to search forward.
  * recent files and packages added to menu
  *