Helping contributors with documentation tools (Hugo "includes")

[mjang]

Is your feature request related to a problem? Please describe

NGINX documentation is built on the static site generator known as Hugo. Our implementation has a concept known as "includes" which support duplicate content.

Sometimes, the duplicated content is so common, it makes life harder for people who want to contribute

Describe the solution you'd like

A solution that helps contributors, which explains:

• What's an include
• Where do you find the include
• How you can contribute with these limitations