[cli] Full config help details

[jimschubert]

Extends the config-help command for formatted output of things like instantiation type mappings, import mappings, etc. Not included here is supporting files because these are almost always set at processOpts time, meaning we'd need to have a dry-run option on the generate command for those outputs.

I haven't enabled the outputs by default. Looking for contributor feedback first. I think this would be an excellent addition to the generator docs that we auto-generate.

Adds boolean options for which output user is looking for, including a full-details option for all.

NAME
openapi-generator-cli config-help - Config help for chosen lang
SYNOPSIS
openapi-generator-cli config-help
[(-f <output format> | --format <output format>)] [--full-details]
[(-g <generator name> | --generator-name <generator name>)]
[--import-mappings] [--instantiation-types]
[--language-specific-primitive] [--markdown-header] [--named-header]
[(-o <output location> | --output <output location>)] [--reserved-words]
OPTIONS
-f <output format>, --format <output format>
Write output files in the desired format. Options are 'text',
'markdown' or 'yamlsample'. Default is 'text'.
--full-details
displays CLI options as well as other configs/mappings (implies
--instantiation-types, --reserved-words,
--language-specific-primitives, --import-mappings,
--supporting-files)
-g <generator name>, --generator-name <generator name>
generator to get config help for
--import-mappings
displays the default import mappings (types and aliases, and what
imports they will pull into the template)
--instantiation-types
displays types used to instantiate simple type/alias names
--language-specific-primitive
displays the language specific primitives (types which require no
additional imports, or which may conflict with user defined model
names)
--markdown-header
When format=markdown, include this option to write out markdown
headers (e.g. for docusaurus).
--named-header
Header includes the generator name, for clarity in output
-o <output location>, --output <output location>
Optionally write help to this location, otherwise default is
standard output
--reserved-words
displays the reserved words which may result in renamed model or
property names

Plain text output example

Formatted markdown output example

PR checklist

• Read the contribution guidelines.
• If contributing template-only or documentation-only changes which will change sample output, build the project before.
• Run the shell script(s) under ./bin/ (or Windows batch scripts under.\bin\windows) to update Petstore samples related to your fix. This is important, as CI jobs will verify all generator outputs of your HEAD commit, and these must match the expectations made by your contribution. You only need to run ./bin/{LANG}-petstore.sh, ./bin/openapi3/{LANG}-petstore.sh if updating the code or mustache templates for a language ({LANG}) (e.g. php, ruby, python, etc).
• File the PR against the correct branch: master, 4.3.x, 5.0.x. Default: master.
• Copy the technical committee to review the pull request if your PR is targeting a particular programming language.

cc @OpenAPITools/generator-core-team

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[jimschubert]

cc @OpenAPITools/generator-core-team

[jimschubert]

I didn't output yamlsample because I'm not sure exactly what this format output is used for, or how the above would fit into that formatted output.