Merge pull request #28 from richardmiller/check-feature-requester-interface

Check feature requester passed in options has the required interface

Author: jkodumal

composer.json

@@ -17,7 +17,7 @@
         "php": ">=5.5"
     },
     "require-dev": {
-        "phpunit/phpunit": "4.3.*",
+        "phpunit/phpunit": "4.8.26",
         "phpdocumentor/phpdocumentor": "2.*",
         "predis/predis": "1.0.*",
         "guzzlehttp/guzzle": "5.*",