Merge pull request #15451 from twbs/bump-remarkable

bump remarkable to ~1.6.0

package.json

@@ -58,7 +58,7 @@
     "grunt-sed": "~0.1.1",
     "load-grunt-tasks": "~1.0.0",
     "npm-shrinkwrap": "^200.0.0",
-    "remarkable": "~1.5.0",
+    "remarkable": "~1.6.0",
     "time-grunt": "~1.0.0"
   },
   "engines": {