how to activate dimensions

I am new to synapse. Thanks so much for these playbooks!

I wasn't sure how you actual activate dimensions after setting these variables. Should you re run 

ansible-playbook -i inventory/hosts setup.yml --tags=setup-all
ansible-playbook -i inventory/hosts setup.yml --tags=start

? If so perhaps you could tell the readers to do this somewhere in the help file

Thanks =]

docs/configuring-playbook-dimension.md

@@ -43,6 +43,13 @@ Add access token to your configuration file (`inventory/host_vars/matrix.<your-d
 matrix_dimension_access_token: "YOUR ACCESS TOKEN HERE"
 ```
 
+After these variables have been set, please run the following command to setup and start dimensions:
+
+```
+ansible-playbook -i inventory/hosts setup.yml --tags=setup-all
+ansible-playbook -i inventory/hosts setup.yml --tags=start
+```
+
 For more information on how to acquire an access token, visit [https://t2bot.io/docs/access_tokens](https://t2bot.io/docs/access_tokens).
 
 ## Additional features