Document all the available runtime config values

[chefsalim]

Ensure attributes of a bound member are documented
Eg: {{cfg.message}}

The config values are documented in an ad-hoc way today (in examples).

[rsertelon]

I'd like to help, but I don't understand what needs to be documented here. Do you talk about {{sys.ip}} etc.?

[rsertelon]

I think this is done in https://www.habitat.sh/docs/reference/#template-data @eeyun maybe you can close this one? :)

[raskchanky]

That does look like the right kind of documentation for what this issue is referring to. If I'm wrong, and there's something not documented there that needs to be, please reopen this.