Add php-cs-fixer to build

.travis.yml

@@ -31,6 +31,7 @@ install:
   - composer install --dev --no-interaction --verbose
 
 script:
+  - vendor/bin/php-cs-fixer fix --config=.php_cs -v --dry-run --diff --using-cache=no
   - php artisan database:create --reset
   - php artisan migrate:refresh --seed
   - cp .travis/phpunit.travis.xml phpunit.xml