chore(npm): Add cpx dependency, add bundle task to ci

.travis.yml

@@ -17,5 +17,5 @@ before_script:
   - echo $JPM_FIREFOX_BINARY
 
 script:
-
+  - npm run bundle
   - npm run travis

package.json

@@ -36,6 +36,7 @@
     "babel-preset-react": "^6.3.13",
     "chai": "^3.5.0",
     "chai-as-promised": "^5.2.0",
+    "cpx": "^1.2.1",
     "eslint": "^1.10.3",
     "eslint-plugin-mozilla": "0.0.3",
     "eslint-plugin-react": "^3.16.1",