Add support for adding messages in closure rules

[kenjis]

This PR makes it possible to add messages in a closure.

        $filter->setRule(
            'foo',
            'Enter Foo correctly',
            function ($value) use ($filter) {
                $pass = true;
                if ($value == '') {
                    $filter->addMessages('foo', 'Foo is required');
                    $pass = false;
                }

                if (! ctype_alpha($value)) {
                    $filter->addMessages('foo', 'Foo should be alpha only');
                    $pass = false;
                }
                return $pass;
            }
        );

[harikt]

Thanks. I had a look into it.

I will leave this to @pmjones to decide :+1: .

Thank you for all the Japanese articles you have been pushing.

[stephen-hill]

I too would like to see this merged please :+1:

[pmjones]

Thanks @kenjis -- multiple rules is something I'd like to avoid, but multiple messages seems OK.

[kenjis]

Thanks for your merging!

[koriym]

@kenjis nice ! :+1: