chore: add codecov (#682)

* chore: add codecov

Add codecov to ShellJS

Partial fix for #671

* Add codecov badge to README

.travis.yml

@@ -29,6 +29,8 @@ script:
   # make sure when the docs are generated nothing changes (a.k.a. the docs have already been generated)
   - npm run gendocs
   - npm run after-travis "Make sure to generate docs!"
+after_success:
+  - codecov
 
 # Gitter
 notifications:

README.md

@@ -3,6 +3,7 @@
 [![Gitter](https://img.shields.io/gitter/room/nwjs/nw.js.svg?style=flat-square)](https://gitter.im/shelljs/shelljs?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 [![Travis](https://img.shields.io/travis/shelljs/shelljs/master.svg?style=flat-square&label=unix)](https://travis-ci.org/shelljs/shelljs)
 [![AppVeyor](https://img.shields.io/appveyor/ci/shelljs/shelljs/master.svg?style=flat-square&label=windows)](https://ci.appveyor.com/project/shelljs/shelljs/branch/master)
+[![Codecov](https://img.shields.io/codecov/c/github/shelljs/shelljs/master.svg?style=flat-square&label=coverage)](https://codecov.io/gh/shelljs/shelljs)
 [![npm version](https://img.shields.io/npm/v/shelljs.svg?style=flat-square)](https://www.npmjs.com/package/shelljs)
 [![npm downloads](https://img.shields.io/npm/dm/shelljs.svg?style=flat-square)](https://www.npmjs.com/package/shelljs)
 

package.json

@@ -54,6 +54,7 @@
   },
   "devDependencies": {
     "ava": "^0.16.0",
+    "codecov": "^1.0.1",
     "coffee-script": "^1.10.0",
     "eslint": "^2.0.0",
     "eslint-config-airbnb-base": "^3.0.0",