chore(package): update markdownlint-cli to version 0.12.0

Closes #213

Author: greenkeeper[bot]

package.json

@@ -80,7 +80,7 @@
     "greenkeeper-lockfile": "1.15.1",
     "jest": "22.4.2",
     "nodemon": "1.17.5",
-    "markdownlint-cli": "0.10.0",
+    "markdownlint-cli": "0.12.0",
     "ramda": "0.25.0",
     "ramda-adjunct": "2.9.0",
     "rimraf": "2.6.2",