add backend readme

closes #77

backend/README.md

@@ -0,0 +1,18 @@
+# Backend for the Simcompanies-Dashboard
+
+## Available Scripts
+
+In the project directory, you can run:
+
+### `yarn start`
+
+Runs the app in the production mode.<br />
+Access the API and frontend files on [http://localhost:3001](http://localhost:3001) to view it in the browser.
+
+### `npm run debug`
+
+Runs the app in the developement mode.<br />
+Access the API and frontend files on [http://localhost:3001](http://localhost:3001) to view it in the browser.
+You can only login with the credentials "test" "test".
+
+The server reloads on changes you still need to refresh your browserpage yourself.