Windows installer - beta release

[Mikhail Glushenkov]

Hi all,

The beta version of the Windows installer is ready and can be
downloaded from

http://code.haskell.org/~refold/HaskellPlatform-2009.0.0-setup.exe

Please test and report any bugs you encounter.

Known issues:

* Installed files are not tracked precisely (we use the Windows
  analogue of rm -rf, which is a bit unsafe).

* OpenAL redistributable is not included (I wasn't sure on
  whether it should be). IIRC, GLUT also doesn't come with
  Windows, so if we decide to include oal_redist.exe, GLUT has to
  be bundled too.

* Branding: it would be nice to have icons with the new logo,
  also for .hs and .lhs files (probably even for the intermediate
  GHC files, like Python does for .pyc). Currently the GHCi
  lambda icon is used.