Merge remote-tracking branch 'origin/current' into rc

source/developers/documentation/standards.markdown

@@ -28,6 +28,8 @@ To ensure that the documentation for Home Assistant is consistent and easy to fo
   * Use `[string, int]` for configuration variables that accept multiple types.
 * Use YAML sequence syntax in the sample code if it is supported.
 * All examples should be formatted to be included in `configuration.yaml` unless explicitly stated.
+  * Use capital letters and `_` to indicate that the value needs to be replaced. E.g., `api_key: YOUR_API_KEY` or `api_key: REPLACE_ME`.
+  * If you know that the API key or value contains [control characters](https://en.wikipedia.org/wiki/YAML#Syntax), e.g., `#`, `[`, `?`, etc., wrap it in quotes and add a note. 
 * Component and platform names should be a link to their respective documentation pages.
 
 ## {% linkable_title Templates %}