add example for free-identifier=? and bound-identifier=? (from the r6rs docs)
add example for free-identifier=? and bound-identifier=? (from the r6rs docs)

mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket