Added blanket.js for code coverage

package.json

@@ -8,12 +8,17 @@
   },
   "main": "index.js",
   "scripts": {
+    "blanket": {
+      "pattern": "//^((?!(node_modules|test)).)*$/"
+    },
+    "coverage": "mocha -r blanket -R html-cov > coverage_loopback-datasource-juggler.html",
     "test": "make test"
   },
   "engines": [
     "node >= 0.6"
   ],
   "devDependencies": {
+    "blanket": "latest",
     "semicov": "*",
     "should": "~1.2.2",
     "mocha": "~1.8.2"