Allow passing an array of flash message as info argument

[niftylettuce]

Per comment in jaredhanson/passport-local#8.

[jaredhanson]

I'm edge-casey on this one. If an app really needs to do this, I'd suggest setting the passReqToCallback option, as so:

passport.use(new LocalStrategy({ passReqToCallback: true }
  function(req, username, password, done) {
    User.findOne({ username: username }, function (err, user) {
      if (err) { return done(err); }
      if (!user) { return done(null, false); }
      if (!user.verifyPassword(password)) {
        req.flash('error', 'Your password is too long');
        req.flash('error, 'Also, it is too short!!!');
        return done(null, false);
      }
      return done(null, user);
    });
  }
));

req becomes the first argument to the verify callback, and you can use it to flash messages to your heart's content.

If enough people +1 this, I'll consider it.