Some fixes, hello-world example (not yet working)

Finding it hard to debug on Windows at least (the compiler's threads seem to be garbling each others output).

One error I got from the C compiler:

c/mingw32/4.7.2/../../../../include/iup/iup.h:13:20: fatal error: iupkey.h: No such file or directory

Maybe an IncludePaths directive is needed in the .use file? I'm not sure