- check in the Gemfile.lock
- use a modern Ruby version
- remove gem upper limits

Revert "Use Homebrew's gitconfig for various commands"

Use Homebrew's gitconfig for various commands

vendor-install: various portable ruby tweaks.

- Rename repository to homebrew-portable-ruby
- Add a new Bintray repository using new name
- Add GitHub releases mirror and try to use it
- Tell people not to file issues if they can't connect to Bintray or
  GitHub: we're not here to provide ISP/proxy support.

cask doctor: sip status

Don't auto-tap caskroom/cask in ZSH completion

brew unlink: fix short option

update brew cask bash completions

The Bash completion just uses the directory tree rather than invoking
`brew cask`, so doesn't exhibit the same behaviour.

Suppress alias expansion in bash completion script

docs: remove :python requirement

Git is a transport and storage mechanism for us so we don't want to
allow arbitrary customisation of this due to user issues e.g. #3664
and #3561.

Fixes #3664.

curl: handle more non-executable curl edge-cases.

Address some additional issues mentioned in #3624.

Interesting-Taps-and-Forks: add brewsci org taps.

From the artist known as homebrew-science.

docs: Fix depends_on examples in Formula page

example:

Error: depends_on :mysql
Correct: depends_on "mysql"

reinstall/upgrade: stop unlinked kegs being sticky

It's not possible to determine the difference between a non-keg-only
keg that failed to link and one that wasn't linked by us intentionally.

To avoid additional complexity of storing this logic in another place
let's back out this relatively new functionality; sticky keg-only links
is a better and more desirable behaviour anyway.

Deprecate Git, Subversion requirements.

These rely on `default_formula` to be useful and are better following
the `*_dep_if_needed` pattern.

formula_cop: match any values in hash match.

check_install_sanity: Use formula.runtime_dependencies

e.g. match an array or symbol or string.

Preserve installed_on_request for dependencies

Cask bash completion

Fix Error: wget contains conflicting version recursive dependencies:
openssl, openssl@1.1

audit: allow env :std in custom taps.

Fixes https://github.com/Homebrew/brew/issues/3642.