add kba-team/typecast to dev requirements

Author: gregor-j

composer.json

@@ -40,7 +40,8 @@
     }
   },
   "require-dev": {
-    "phpunit/phpunit": "^4.8"
+    "phpunit/phpunit": "^4.8",
+    "kba-team/typecast": "^1.0"
   },
   "scripts": {
     "tests": "vendor/bin/phpunit"