Initial yaml fixer version

Author: akovalyov

composer.json

@@ -11,7 +11,8 @@
     ],
     "require": {
         "php": ">=5.4",
-        "fabpot/php-cs-fixer": "^1.10"
+        "fabpot/php-cs-fixer": "^1.10",
+        "symfony/yaml": "~2.7"
     },
     "require-dev": {
         "phpunit/phpunit": "^4.8"