add PaaS section, move items from awesome-selfhosted (#570)

* add PaaS section, move items from awesome-selfhosted
* ref. https://github.com/awesome-selfhosted/awesome-selfhosted-data/pull/608
* add nhost to PaaS section
* doc: update PaaS section description, include serverless/FaaS software
* add fx, OpenFaaS and Trusted-CGI to PaaS section

README.md

@@ -38,6 +38,7 @@
   - [Miscellaneous](#miscellaneous)
   - [Monitoring](#monitoring)
   - [Network Configuration Management](#network-configuration-management)
+  - [PaaS](#paas)
   - [Packaging](#packaging)
   - [Project Management](#project-management)
   - [Queuing](#queuing)
@@ -531,6 +532,25 @@ Network configuration management tools.
 - [rConfig](https://www.rconfig.com/) - Network device configuration management tool. ([Source Code](https://github.com/rconfig/rconfig)) `GPL-3.0` `PHP`
 
 
+### PaaS
+
+**[`^        back to top        ^`](#awesome-sysadmin)**
+
+[Platform-as-a-Service](https://en.wikipedia.org/wiki/Platform_as_a_service) software allows customers to provision, instantiate, run, and manage a computing platform and one or more applications, without the complexity of building and maintaining the infrastructure typically associated with developing and launching the application. Also includes [Serverless computing](https://en.wikipedia.org/wiki/Serverless_computing) and [Function-as-a-service (FaaS)](https://en.wikipedia.org/wiki/Function_as_a_service) software.
+
+
+- [CapRover](https://caprover.com/) - Build your own PaaS in a few minutes. ([Demo](https://captain.server.demo.caprover.com/#/login), [Source Code](https://github.com/caprover/caprover)) `Apache-2.0` `Docker/Nodejs`
+- [Coolify](https://coolify.io/) - An open-source & self-hostable Heroku / Netlify alternative (and even more). ([Source Code](https://github.com/coollabsio/coolify)) `Apache-2.0` `Docker`
+- [Dokku](https://dokku.com/) - An open-source PaaS (alternative to Heroku). ([Source Code](https://github.com/dokku/dokku)) `MIT` `Docker/Shell/Go/deb`
+- [fx](https://github.com/metrue/fx) - A tool to help you do Function as a Service with painless on your own servers. `MIT` `Go`
+- [Kubero](https://www.kubero.dev/) - A self-hosted Heroku PaaS alternative for Kubernetes that implements GitOps. ([Demo](https://demo.kubero.dev/), [Source Code](https://github.com/kubero-dev/kubero)) `GPL-3.0` `K8S/Nodejs/Go`
+- [LocalStack](https://localstack.cloud/) - LocalStack is a fully functional local AWS cloud stack. This includes Lambda for serverless computation. ([Source Code](https://github.com/localstack/localstack)) `Apache-2.0` `Python/Docker/K8S`
+- [Nhost](https://nhost.io/) - Firebase Alternative with GraphQL. Get a database and backend configured and ready in minutes. ([Source Code](https://github.com/nhost/nhost)) `MIT` `Docker/Nodejs/Go`
+- [OpenFaaS](https://www.openfaas.com/) - Serverless Functions Made Simple for Docker & Kubernetes. ([Source Code](https://github.com/openfaas/faas)) `MIT` `Go`
+- [Trusted-CGI](https://github.com/reddec/trusted-cgi) - Lightweight self-hosted lambda/applications/cgi/serverless-functions platform. `MIT` `Go/deb/Docker`
+
+
+
 ### Packaging
 
 **[`^        back to top        ^`](#awesome-sysadmin)**