chore(package): update coveralls to version 3.0.0 (#51)

Author: greenkeeper[bot]

package.json

@@ -28,7 +28,7 @@
   "homepage": "https://github.com/yargs/y18n",
   "devDependencies": {
     "chai": "^4.0.1",
-    "coveralls": "^2.11.6",
+    "coveralls": "^3.0.0",
     "mocha": "^3.0.0",
     "nyc": "^11.0.1",
     "rimraf": "^2.5.0",