Here's what you need to do:
In the same directory where you have package.json create an npm-shrinkwrap.json file with the following contents:
{
"dependencies": {
"graceful-fs": {
"version": "4.2.2"
}
}
}Run npm install, and don't worry, it'll update npm-shrinkwrap.json with a bunch of content.
Now, fire your gulp command and enjoy, it should be working just fine!