feat: add dotenv.dist format

[slashformotion]

goal: provide an informative .env.dist files to fill out directly by the different teams that are using the software configured using environment variables.

why I am not using the existing dotenv format ? the dotenv format has some # before the env vars. This makes some teams at my workplace wonder what they should uncomment.

[g4s8]

Thanks for submitting! Changes look reasonable, but these two formats for dotenv and dotenv.dist look very similar. So I would add some additional flag for dotenv as a format option instead of creating a new format. E.g. when the -dist flag is present, then the dotenv format renders env variable names without comment. What do you think about this?

[slashformotion]

LGTM, I will look into implementing it

[slashformotion]

After tinkering a little bit, I think it's way easier to just introduce a new template, passing a flag value will probably be fine for one flag, but with time it will be a mess if more flags are added.

An alternative would be to support custom templates, but it's probably another can of worm.