update author information in the Windows installer
drop support for proprietary Cg on Windows

point to https://developer.nvidia.com/cg-toolkit-download
bundle Windows dependencies inside the installer

http://libsdl.org/release/SDL-1.2.15-win32.zip
http://kcat.strangesoft.net/openal-soft-1.15.1-bin.zip
http://sourceforge.net/projects/gnuwin32/files/freetype/2.3.5-1/freetype-2.3.5-1-bin.zip
http://sourceforge.net/projects/gnuwin32/files/zlib/1.2.3/zlib-1.2.3-bin.zip/download
update documentation for simplified dependencies
we only require non-CLI binaries to build
expose the new portable Support directory to Win installer

closes #3673
Merge pull request #3819 from Mailaender/nsis-dependencies

Bundled native Windows dependencies