Today the Homebrew maintainers elected a new PLC, TSC and project lead.
Documentation is to follow detailing exactly the responsibilities for
each of these roles but adjust these to reflect the current state until
that point.

Also, cleanup usage of `<formula>`.

As requested in comments of #5587.

And guard against either of them being missing.

Fixes #5610

And remove all dead/unneeded code.

Update for the pending 2.0.0 release which will support Linux.

As requested in:
https://github.com/Homebrew/brew/issues/5615#issuecomment-457816870

- Move `odeprecated` to `odisabled`
- Remove `odisabled`
- Enable automatic cleanup on install/reinstall/upgrade.

Use the nice homebrew-core ones instead.

Bumps [html-proofer](https://github.com/gjtorikian/html-proofer) from 3.10.1 to 3.10.2.
- [Release notes](https://github.com/gjtorikian/html-proofer/releases)
- [Commits](https://github.com/gjtorikian/html-proofer/compare/v3.10.1...v3.10.2

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Bumps [parallel](https://github.com/grosser/parallel) from 1.12.1 to 1.13.0.
- [Release notes](https://github.com/grosser/parallel/releases)
- [Commits](https://github.com/grosser/parallel/compare/v1.12.1...v1.13.0

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Bumps [html-proofer](https://github.com/gjtorikian/html-proofer) from 3.10.0 to 3.10.1.
- [Release notes](https://github.com/gjtorikian/html-proofer/releases)
- [Commits](https://github.com/gjtorikian/html-proofer/compare/v3.10.0...v3.10.1

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

This change fixes a syntax error introduced in b278165d

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.10.0 to 1.10.1.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/master/CHANGELOG.md)
- [Commits](https://github.com/sparklemotion/nokogiri/compare/v1.10.0...v1.10.1

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

If set, Homebrew will fail if on the failure of installation from a
bottle rather than falling back to building from source.

Bumps [ethon](https://github.com/typhoeus/ethon) from 0.11.0 to 0.12.0.
- [Release notes](https://github.com/typhoeus/ethon/releases)
- [Changelog](https://github.com/typhoeus/ethon/blob/v0.12.0/CHANGELOG.md)
- [Commits](https://github.com/typhoeus/ethon/compare/v0.11.0...v0.12.0

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Please see https://discourse.brew.sh/t/bash-completion-and-brew-instructions-for-setting-up-completions/3808 for details...

- Add some `odeprecated`
- Make some `odeprecated` now `odisabled`
- Remove `odisabled` code.
- Remove old update migrations
- Remove GCC 4.0 compiler
- Remove Tiger-only code
- Remove 32-bit-only code
- Remove use of LD64
- Remove GCC 4.3 - 4.8 support.

Bumps [html-pipeline](https://github.com/jch/html-pipeline) from 2.9.2 to 2.10.0.
- [Release notes](https://github.com/jch/html-pipeline/releases)
- [Changelog](https://github.com/jch/html-pipeline/blob/master/CHANGELOG.md)
- [Commits](https://github.com/jch/html-pipeline/compare/v2.9.2...v2.10.0

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Bumps [ffi](https://github.com/ffi/ffi) from 1.9.25 to 1.10.0.
- [Release notes](https://github.com/ffi/ffi/releases)
- [Changelog](https://github.com/ffi/ffi/blob/master/CHANGELOG.md)
- [Commits](https://github.com/ffi/ffi/compare/1.9.25...1.10.0

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Bumps [html-pipeline](https://github.com/jch/html-pipeline) from 2.9.1 to 2.9.2.
- [Release notes](https://github.com/jch/html-pipeline/releases)
- [Changelog](https://github.com/jch/html-pipeline/blob/master/CHANGELOG.md)
- [Commits](https://github.com/jch/html-pipeline/compare/v2.9.1...v2.9.2

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Bumps [html-proofer](https://github.com/gjtorikian/html-proofer) from 3.9.3 to 3.10.0.
- [Release notes](https://github.com/gjtorikian/html-proofer/releases)
- [Commits](https://github.com/gjtorikian/html-proofer/compare/v3.9.3...v3.10.0

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Bumps [sass](https://github.com/sass/ruby-sass) from 3.7.2 to 3.7.3.
- [Release notes](https://github.com/sass/ruby-sass/releases)
- [Commits](https://github.com/sass/ruby-sass/compare/3.7.2...3.7.3

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

This is already accepted so let's handle this in the logic instead.

This will become the default in a later version of Homebrew but has an
opt-out through HOMEBREW_NO_INSTALL_CLEANUP.

Also, always cleanup files older than 120 days and set the general
default value for "old" logs, casks etc. to 30 days.

Minor fix to improve readability.

It's always seemed a bit pointless to me that we have both of these
commands. Given we're doing more and more to recommend (and eventually,
safely, automatically run (see #4760) `brew cleanup` let's roll their
functionality into a single command.

This simplifies the process of vendoring gems given `Gemfile` or
`Gemfile.lock` changes.

Bumps [unicode-display_width](https://github.com/janlelis/unicode-display_width) from 1.4.0 to 1.4.1.
- [Release notes](https://github.com/janlelis/unicode-display_width/releases)
- [Changelog](https://github.com/janlelis/unicode-display_width/blob/master/CHANGELOG.md)
- [Commits](https://github.com/janlelis/unicode-display_width/compare/v1.4.0...v1.4.1

)

Signed-off-by: dependabot[bot] <support@dependabot.com>