Added build script in package.json

Author: Thomas Imart

package.json

@@ -27,6 +27,7 @@
     "url": "https://github.com/openstf/adbkit.git"
   },
   "scripts": {
+    "build": "coffee -c -o lib src",
     "postpublish": "grunt clean",
     "prepublish": "grunt test coffee",
     "test": "grunt test"
@@ -61,4 +62,4 @@
   "engines": {
     "node": ">= 0.10.4"
   }
-}
+}