vocabs.platforms: Add some more experimental USE: style words.
vocabs.platforms: Add some more experimental USE: style words.

examples:

USE-IF: roman [ os macosx? ]

USE-UNIX: io.unix

USE-WINDOWS: windows

  old:
{
    { [ os windows? ] [ "alien.libraries.windows" ] }
    { [ os unix? ] [ "alien.libraries.unix" ] }
} cond require

  new:
USE-WINDOWS: alien.libraries.windows
USE-UNIX: alien.libraries.unix

factor/factor,tgunr/factor,mrjbq7/factor,factor/factor,factor/factor,factor/factor,mrjbq7/factor,factor/factor,factor/factor,mrjbq7/factor,tgunr/factor,mrjbq7/factor,mrjbq7/factor,tgunr/factor,mrjbq7/factor,tgunr/factor,tgunr/factor,tgunr/factor