prepublish script

Author: Artur Charaev

package.json

@@ -6,6 +6,7 @@
   "scripts": {
     "build": "babel src --out-dir lib",
     "clean": "rimraf lib",
+    "prepublish": "npm run clean && npm run build",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "keywords": [
@@ -26,5 +27,10 @@
     "babel-plugin-transform-object-rest-spread": "^6.20.2",
     "babel-preset-es2015": "^6.18.0",
     "rimraf": "^2.5.4"
-  }
+  },
+  "files": [
+    "README.md",
+    "LICENSE.md",
+    "lib"
+  ]
 }