[sluggable] updates transliterator version

Since it introduced backward incompatible change

Author: l3pp4rd

composer.json

@@ -39,7 +39,7 @@
     },
     "require": {
         "php": ">=5.3.2",
-        "behat/transliterator": "~1.0",
+        "behat/transliterator": "1.1",
         "doctrine/common": "~2.4"
     },
     "require-dev": {