Add `Formatter` module.

Library/Homebrew/brew.rb

Library/Homebrew/cask/lib/hbc/artifact/moved.rb

Library/Homebrew/cask/lib/hbc/artifact/symlinked.rb

Library/Homebrew/cask/lib/hbc/checkable.rb

Library/Homebrew/cask/lib/hbc/cli/doctor.rb

Library/Homebrew/cask/lib/hbc/cli/info.rb

Library/Homebrew/cask/lib/hbc/installer.rb

Library/Homebrew/cask/lib/hbc/utils.rb

Library/Homebrew/cmd/doctor.rb

Library/Homebrew/cmd/info.rb

Library/Homebrew/descriptions.rb

Library/Homebrew/dev-cmd/bottle.rb

Library/Homebrew/exceptions.rb

Library/Homebrew/formula_installer.rb

Library/Homebrew/migrator.rb

Library/Homebrew/utils.rb

Library/Homebrew/utils/formatter.rb

Library/Homebrew/utils/github.rb