To avoid extra work on the part of contributors and maintainers, this
adds a step to the explanation of how to contribute a fix to a formula,
showing how to check if someone else has already done so, even if it
has not yet finished being tested, reviewed, and released.
ClosesHomebrew/homebrew#48879.
Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
Remove duplication, link to the API documentation more often,
tweak wording, add `@UniqMartin` as a maintainer, note `@jacknagel`'s
and `@adamv`'s significant past contributions to Homebrew, delete some
outdated or unneeded documentation, add some missing `Formula` API.
entries and simplify/improve `CONTRIBUTING.md`.
ClosesHomebrew/homebrew#46179.
ClosesHomebrew/homebrew#46618.
Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>