Merge branch 'improve-initial-setup-procedure' into 'master'

update readme; add helper yarn commands

See merge request saburly/gangsta/roraccounting!1

package.json

@@ -10,5 +10,11 @@
   },
   "dependencies": {
     "react-router-dom": "^5.0.1"
+  },
+
+  "scripts": {
+    "dev-db": "docker run --name gangstadb -d -p 5432:5432 -e POSTGRES_PASSWORD=docker -e POSTGRES_DB=roraccounting_development roraccounting",
+    "server": "PORT=3001 bundle exec rails s",
+    "client": "PORT=3000 yarn --cwd client start"
   }
 }