Add Dossier to headless cms list

Author: jonasb

src/site/headless-cms/dossier.md

@@ -0,0 +1,19 @@
+---
+title: Dossier
+homepage: https://www.dossierhq.dev
+repo: dossierhq/dossierhq
+opensource: "Yes"
+typeofcms: "API Driven"
+supportedgenerators:
+  - All
+description: Dossier is an open source toolkit for building headless CMSs.
+---
+
+Dossier enables you to build solutions where you’re in full control of the content. By bringing your own auth (authentication and authorization), database and backend, you can build a headless Content Management System (CMS) and integrate it with your app.
+
+## Resources
+
+* [Documentation](https://www.dossierhq.dev/docs)
+* [Playground](https://playground.dossierhq.dev/)
+* [Getting started](https://www.dossierhq.dev/docs/getting-started)
+* [Blog](https://www.dossierhq.dev/blog)