Minimum node version added to package.json

Author: ivanalemunioz

package.json

@@ -24,5 +24,6 @@
     "node-forge": "^0.8.5",
     "soap": "^0.24.0",
     "xml2js": "^0.4.22"
-  }
+  },
+  "engines" : { "node" : ">=7.0" }
 }