add link

plugins/gulp/README.md

 # gulp plugin
 
-This plugin adds autocompletion for your `gulp` tasks. It grabs all available tasks from the `gulpfile.js` in the current directory.
+This plugin adds autocompletion for your [`gulp`](https://gulpjs.com/) tasks. It grabs all available tasks from the `gulpfile.js` in the current directory.
 
 To use it, add `gulp` to the plugins array of your `.zshrc` file:
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