[5pt] List all Cartridge container environment variables in one place

Product: Cartridge
Audience/target: dev
Root document: https://www.tarantool.io/en/doc/latest/book/cartridge/cartridge_dev/?
SME: @ sergos
Peer reviewer: @ NickVolynkin?

Details

Looks like information on environment variables is hard to find in Cartridge building docs.
It is provided here: https://www.tarantool.io/en/doc/latest/book/cartridge/cartridge_api/modules/cartridge/#cartridge-cfg
and here:
https://www.tarantool.io/en/doc/latest/book/cartridge/cartridge_cli/#environment-variables

I see two options:

• Provide a link to https://www.tarantool.io/en/doc/latest/book/cartridge/cartridge_api/modules/cartridge/#cartridge-cfg from Cartridge Developer's Guide. A good place would be item 2 of the numbered list (easier, a workaround)
• Condense the variables and the corresponding flags/options in a separate page, describing them and providing cross-references. This might have the form of a table. (harder but more user-friendly)

This is a comment to a Mail.ru expert article about Cartridge CLI:

"Try finding a list of environment variables that are used to configure Tarantool in a Cartridge container. I didn't found this in the doc. But I did in cartridge.yaml in a freshly generated application. It's only logical, but please describe this in the documentation."

"Попробуйте найти список переменных окружения используемых для конфигурации тарантула в контейнере картриджа. В документации этого я не нашёл. Знаете где? В файлике cartridge.yaml во вновь сгенерённом приложении. С одной стороны логично, с другой - в документации опишите." https://habr.com/en/company/mailru/blog/571936/#comment_23359672

Review the Cartridge Developer's Guide configuration basics and the existing cartridge-cfg and Cartridge CLI environment-variables sections linked in the issue. Choose whether to add the cross-reference or create a consolidated table, then verify that the relevant variables and options are documented and discoverable from the developer guide.