Blender Git Loki

* rewrote part of the targets code
* added 'scons wininst'. This will create a NSIS installer for blender.
This will need the NSIS tool in your path (makensis.exe).
The needed scriptfile will be committed seperately, so remember
to 'cvs update -d'

* tested on windows and linux, so other platform maintainers, please
check that the build process is not broken.