`Expect::anyOf` should not disable `before()`

[ViliamKopecky]

Version: v1.0.2

Bug Description

before() helper is not called on things nested in Expect::anyOf.

Steps To Reproduce

test(function() { // normalization through anyOf
	$schema = Expect::anyOf(Expect::string()->before(function($v) {
		return (string) $v;
	}));
	Assert::same('1',  $schema->normalize(1, new Context));
});

Expected Behavior

before() should work consistently inside anyOf.