improve test

.travis.yml

@@ -1,6 +1,3 @@
 language: node_js
 node_js:
-  - "4.0"
-before_script:
-  - npm install -g gulp
-script: gulp release
+  - "4.0"

README.md

@@ -173,6 +173,7 @@ $ npm run dev
 ## Make a release
 
 ```
+$ npm install
 $ npm run build
 ```
 

package.json

@@ -4,7 +4,7 @@
   "description": "Wow, such a beautiful html5 music player",
   "main": "dist/APlayer.min.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1",
+    "test": "gulp release",
     "dev": "gulp",
     "build": "gulp release"
   },