Format for documenting variables and placeholders?

[tang-mm]

Suggestions from the Google style guide:

• wrapping placeholders in a element and use uppercase characters with underscore delimiters, such as PROJECT_ID
• In Markdown, wrap inline placeholders in backticks (), and use an asterisk (*) before the first backtick and after the second one (*PLACEHOLDER_NAME`*).
• If the context in which your placeholders appear makes using uppercase characters with underscore delimiters a bad idea, use something else that makes sense to you, but be internally consistent.

However, in our templates, curly braces { } have been commonly used. We should have a set of guidelines regarding the format.

See the related review comment

[heykayla]

Agreed to continue using curly brackets for both placeholder text and writer's notes.