raco setup: flush loaded "info-domain" when info is updated
raco setup: flush loaded "info-domain" when info is updated

Fixes problems updating user-specific documentation on a
package install, for example.

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