Contributor path for translating docs into additional languages

[displague]

Expected Behaviour

Contributors should have a path for offering additional languages to the Tinkerbell documentation.

Current Behaviour

English is the only language provided. There is no documentation on how to add additional languages.

Possible Solution

mkdocs offers translation documentation here:
https://www.mkdocs.org/dev-guide/translations/

• Stub out any production needs for offering additional languages.
• Add contributing steps here: https://docs.tinkerbell.org/contrib/

Context

In the 2021-07-05 community call, a Korean translation was proposed by a new community member.