Functionality to link users to helper documentation

[pradyunsg]

pip's documentation contains a dedicated section describing how the NEWS file fragments should be written.

https://pip.pypa.io/en/latest/development/contributing/#news-entries

Ideally, we'd like to be able to configure Chronographer to link to it.

[pradyunsg]

Related: #10

[webknjaz]

It'd say it's a duplicate of #10. I was also thinking maybe to teach it .. include:: things so that you could just point the config to a chunk of md/rst and make it show up right on that page...

[webknjaz]

@pradyunsg I can't decide on how/what needs to be exposed in the config. So far, I've sketched this. Ideas? Bikeshedding?

---

action-hints:
  external-docs-url: https://pip.pypa.io/how-to-changelog
  include-inline-markdown: >
    Check out https://pip.pypa.io/how-to-changelog
  include-inrepo-markdown: how-to-changelog.md  # needs an extra API call
  show: on-failure | always

...

[pradyunsg]

TBH, pip pretty much only needs the docs URL, and it's likely easier to just always show things -- so, I'd say just the following would be enough:

action-hints:
  external-docs-url: https://pip.pypa.io/how-to-changelog

[webknjaz]

@pradyunsg would you say that https://github.com/sanitizers/chronographer-github-app/commit/a2a81e8310fe5ba8ea5f8fd99f6ebf666f1d76bf, https://github.com/sanitizers/chronographer-github-app/commit/70867ed8bae8c796a76f64d338da5ae952ca5be7 and https://github.com/sanitizers/chronographer-github-app/commit/a0e61fc0451134439c7dd328eb5ef2f05b186f90 implement this?

Resolve if you agree.

[pradyunsg]

LGTM!