Add Laravel 9 support (calebporzio#103)

* Update constraints

* Update tests workflow

* Update orchestra/database constraint

* Fix which Laravel version is tested on which PHP version

add DB validation rule info to readme (calebporzio#95)

wip

Update tests.yml (calebporzio#83)

* Update tests.yml

* Update tests.yml

* Update composer.json

Changed doctrine/dbal to ^2.9, as the ^2.10 constraint excludes support for PHP 7.1

* Add skipped group to skipped tests

Merge pull request calebporzio#81 from viezel/php8support

PHP 8 Support

Merge pull request calebporzio#72 from incredimike/fix-country-example

Corrected country example labelling

Add getSchema and $schema functionality

Support Laravel 7

Fix timestamps

Add timestamps if not specified