IWD project type

[JezuzLizard]

In CoDs older than T6 IWDs were used to store assets for raw loading such as rawfiles, scripts, images, streamed sounds etc. An IWD is just a normal zip file compressed using zlib, just with .iwd extension. While not strictly necessary to add since it is trivial to just zip up the files and rename the file extension to iwd, the canonical mod tools do have an iwd list for the linker to know what files go into iwds and then the linker will create the iwd with the assets.