Documentation skeleton (#1617)

* Documentation skeleton

* Added ADR list and more

* rm material theme

* Update mkdocs.yml

* Add docs TOC

* Work for plain MD and mkdocs

* Update mkdocs.yml

* Restructuring

* Added roadmap

* Add reference APIs

* move publishing

docs/plugins/create-a-plugin.md

@@ -0,0 +1,43 @@
+# Create a Backstage Plugin
+
+A Backstage Plugin adds functionality to Backstage.
+
+## Create a Plugin
+
+To create a new plugin, make sure you've run `yarn install` and installed
+dependencies, then run the following on your command line (invoking the
+`backstage-cli`).
+
+```bash
+yarn create-plugin
+```
+
+<p align='center'>
+    <img src='https://github.com/spotify/backstage/raw/master/docs/getting-started/create-plugin_output.png' width='600' alt='create plugin'>
+</p>
+
+This will create a new Backstage Plugin based on the ID that was provided. It
+will be built and added to the Backstage App automatically.
+
+_If `yarn start` is already running you should be able to see the default page
+for your new plugin directly by navigating to
+`http://localhost:3000/my-plugin`._
+
+<p align='center'>
+    <img src='https://github.com/spotify/backstage/raw/master/docs/getting-started/my-plugin_screenshot.png' width='600' alt='my plugin'>
+</p>
+
+You can also serve the plugin in isolation by running `yarn start` in the plugin
+directory. Or by using the yarn workspace command, for example:
+
+```bash
+yarn workspace @backstage/plugin-welcome start # Also supports --check
+```
+
+This method of serving the plugin provides quicker iteration speed and a faster
+startup and hot reloads. It is only meant for local development, and the setup
+for it can be found inside the plugin's `dev/` directory.
+
+[Next Step - Structure of a plugin](structure-of-a-plugin.md)
+
+[Back to Getting Started](README.md)