Merge pull request #2698 from reitermarkus/operator-style

Library/.rubocop.yml

.../Homebrew/cask/lib/hbc/cli/internal_appcast_checkpoint.rb

Library/Homebrew/cmd/list.rb

Library/Homebrew/cmd/search.rb

Library/Homebrew/cmd/switch.rb

Library/Homebrew/debrew.rb

Library/Homebrew/dev-cmd/audit.rb

Library/Homebrew/dev-cmd/bottle.rb

Library/Homebrew/dev-cmd/edit.rb

Library/Homebrew/development_tools.rb

Library/Homebrew/diagnostic.rb

Library/Homebrew/download_strategy.rb

Library/Homebrew/exceptions.rb

Library/Homebrew/extend/ARGV.rb

Library/Homebrew/extend/ENV/std.rb

Library/Homebrew/extend/os/mac/extend/ENV/std.rb

Library/Homebrew/extend/pathname.rb

Library/Homebrew/formula.rb

Library/Homebrew/formula_cellar_checks.rb

Library/Homebrew/formula_installer.rb