Merge pull request #15 from nodaguti/greenkeeper-textlint-tester-2.0.0

Update textlint-tester to version 2.0.0 🚀

Author: nodaguti

package.json

@@ -41,6 +41,6 @@
     "npm-run-all": "^2.1.2",
     "power-assert": "^1.4.1",
     "textlint": "^6.11.1",
-    "textlint-tester": "^1.2.0"
+    "textlint-tester": "^2.0.0"
   }
 }