Add missing dependency

package.json

@@ -28,6 +28,7 @@
     "chai": "^3.5.0",
     "istanbul": "1.1.0-alpha.1",
     "mocha": "^3.0.2",
+    "raml2html": "^3.0.0",
     "tslint": "^3.14.0",
     "tslint-stylish": "^2.1.0-beta"
   }