setup codeclimate for codecoverage reporting

.travis.yml

 language: node_js
 node_js:
   - 'node'
+before_install:
+  - curl -L https://codeclimate.com/downloads/test-reporter/test-reporter-latest-linux-amd64 > ./cc-test-reporter
+  - chmod +x ./cc-test-reporter
+
 before_script:
   - npm install
+
+# Pipe the coverage data to Code Climate
+after_script:
+  - ./cc-test-reporter after-build --exit-code $TRAVIS_TEST_RESULT