dmd, x64 and Windows

[Andrej Mitrovic]

No problem. Make sure you follow the latest one because there's
another patch you have to use to make stdio work (I've posted this on
SO already). I've also added some info on where to get GDB and its
manuals. Using GDB works great, the symbols get loaded from the
executable when compiled with 'GDC -g file.d'.

Here's the latest one: https://gist.github.com/857381