Added Hashnode Headless (#950)

* Added Hashnode Headless

* Fixed twitter

---------

Co-authored-by: Haimantika Mitra <haimantikamitra@Haimantikas-MacBook-Pro.local>

Author: Haimantika

src/site/headless-cms/headless-hashnode.md

@@ -0,0 +1,21 @@
+---
+title: Hashnode Headless CMS
+homepage: https://hashnode.com/headless
+twitter: hashnode
+opensource: "Yes"
+typeofcms: "API Driven"
+supportedgenerators:
+  - All
+description: A purpose built Headless CMS that can help yop integrate your blog seamlessly on any custom domain including sub-paths like/blog for complete branding control.
+---
+## About Hashnode Headless CMS
+Hashnode is blogging platform for developers with free public GraphQL APIs, WYSIWYG editor, AI support and more. It's Headless CMS offering allows you to leverage Hashnode's advanced GraphQL APIs to construct your blog's homepage, articles, comments, search functionality, and more with full customisation. It lets you deploy your custom-built blog on any hosting service, domain, or even using sub-paths like /blog.
+
+## Useful Links to get Started with Hashnode Headless CMS
+https://hashnode.com/headless
+
+#### Reach out to us for more information:
+https://hashnode.com/headless#pricing
+
+#### Get started for free:
+https://github.com/Hashnode/starter-kit