fixed check-regexp-match so that the test suite fails when the argument isn't a string (instead of signalling an internal error)
fixed check-regexp-match so that the test suite fails when the argument isn't a string (instead of signalling an internal error)

svn: r16361

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