message: docs(languages): adding documentation for available page languages
diff: @@ -46,6 +46,20 @@ For English used in the United Kingdom, specify:
  the country identifier should be written in uppercase following usual
  conventions.
  +### Configuring available languages
  +
  +The available languages are set by the following tags within `<head>`:
  +
  +```html
  +<link rel="alternate" hreflang="[language code]-[country code]" href="[redirect link]">
  +```
  +
  +For example:
  +
  +```html
  +<link rel="alternate" hreflang="en-us" href="https://www.ibm.com/us-en/">
  +```
  +
  ## Digital data object
  The Digital Data Object (DDO) is a critical part of any page. It is a flexible,
  