cmd, cask: info prints whether installed

Library/Homebrew/cask/info.rb

@@ -48,7 +48,7 @@ module Cask
         Formatter.error("does not exist")
       end
 
-      "#{versioned_staged_path} (#{path_details})\n"
+      "Installed\n#{versioned_staged_path} (#{path_details})\n"
     end
 
     def self.name_info(cask)

Library/Homebrew/cmd/info.rb

@@ -301,6 +301,7 @@ module Homebrew
         if kegs.empty?
           puts "Not installed"
         else
+          puts "Installed"
           kegs.each do |keg|
             puts "#{keg} (#{keg.abv})#{" *" if keg.linked?}"
             tab = Tab.for_keg(keg).to_s

Library/Homebrew/cmd/tap-info.rb

@@ -64,6 +64,7 @@ module Homebrew
             puts unless i.zero?
             info = "#{tap}: "
             if tap.installed?
+              info += "Installed"
               info += if (contents = tap.contents).blank?
                 "no commands/casks/formulae"
               else