build: bump backports from 3.14.0 to 3.15.0 in /Library/Homebrew

Homebrew-on-Linux.md: update minimal requirements

Bumps [backports](https://github.com/marcandre/backports) from 3.14.0 to 3.15.0.
- [Release notes](https://github.com/marcandre/backports/releases)
- [Changelog](https://github.com/marcandre/backports/blob/master/CHANGELOG.rdoc)
- [Commits](https://github.com/marcandre/backports/compare/v3.14.0...v3.15.0

)

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

These are needed to build patchelf 0.10 with debian wheezy.

utils/github: better handle blank scopes.

python_virtualenv_constants: upgrade virtualenv to 16.6.0

If both provided and required scopes are blank then we cannot display a
good error message so don't try.

Fixes #6134.

Add exception for veclibfort linking to Accelerate

 - veclibfort exists soley to wrap Apple's accelerate and provide BLAS/LAPACK
   access to Accelerate
 - Improve the help message for that audit to mention veclibfort

 - Method alignment was bad across line break in 3 places.

Add a blank line between `brew cask info` output for multiple casks

audit: check Accelerate linkage for core formulae

build: bump multipart-post from 2.1.0 to 2.1.1 in /docs

Add bump-revision command

Bumps [multipart-post](https://github.com/nicksieger/multipart-post) from 2.1.0 to 2.1.1.
- [Release notes](https://github.com/nicksieger/multipart-post/releases)
- [Changelog](https://github.com/socketry/multipart-post/blob/master/History.txt)
- [Commits](https://github.com/nicksieger/multipart-post/compare/v2.1.0...v2.1.1

)

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

docs/Homebrew-on-Linux: Fedora 30 needs libxcrypt-compat

portable-ruby requires the library libcrypt.so.1.
On Fedora 30, that file is provided by libxcrypt-compat.

- `brew info` adds a blank line between info output for multiple
  formulae. This replicates that display for `brew cask info`, as
  requested in Issue 6126.

build: bump rubocop from 0.68.1 to 0.69.0 in /Library/Homebrew

Merge remote-tracking branch 'origin/dependabot/bundler/Library/Homebrew/rubocop-rspec-1.33.0' into dependabot/bundler/Library/Homebrew/rubocop-0.69.0

Bumps [rubocop-rspec](https://github.com/rubocop-hq/rubocop-rspec) from 1.32.0 to 1.33.0.
- [Release notes](https://github.com/rubocop-hq/rubocop-rspec/releases)
- [Changelog](https://github.com/rubocop-hq/rubocop-rspec/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rubocop-hq/rubocop-rspec/compare/v1.32.0...v1.33.0

)

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

Bumps [rubocop](https://github.com/rubocop-hq/rubocop) from 0.68.1 to 0.69.0.
- [Release notes](https://github.com/rubocop-hq/rubocop/releases)
- [Changelog](https://github.com/rubocop-hq/rubocop/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rubocop-hq/rubocop/compare/v0.68.1...v0.69.0

)

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

teach brew about mksh

pkgconfig: add uuid.pc

formula_creator: fix meson template

* meson-internal should not be used for new formulas anymore, as the
latest releases of meson have proper support for macOS now.
* make ninja commands verbose

The util-linux uuid library is provided by macOS, through its header at
/usr/include/uuid/uuid.h, and implementation included in libSystem.B.dylib

azure-pipelines: use 10.14 (and Swift)

See https://github.com/Homebrew/brew/pull/6083

See https://github.com/Homebrew/brew/pull/6083

This avoids hitting AppleScript timeouts in CI.

Taps: remove references to pinning.