add php-cs-fixer into travis tasks

.php_cs

@@ -1,6 +1,6 @@
 <?php
 
 $config = new Symfony\CS\Config\Config();
-$config->getFinder()->exclude('bin');
+$config->getFinder()->in(__DIR__)->exclude('bin');
 
 return $config;

.travis.yml

@@ -1,4 +1,12 @@
 language: php
+
+before_script:
+  - curl http://cs.sensiolabs.org/get/php-cs-fixer.phar -o php-cs-fixer.phar
+
+script:
+  - phpunit
+  - php php-cs-fixer.phar --dry-run -v fix .
+
 php:
   - 5.2
   - 5.3