Add Cask#outdated_info to format output

Library/Homebrew/cask/cask.rb

@@ -122,6 +122,21 @@ module Cask
       installed.reject { |v| v == version }
     end
 
+    def outdated_info(greedy, verbose, json)
+      if json
+        {
+          name: token,
+          installed_versions: outdated_versions(greedy).join(", "),
+          current_version: version
+        }
+      elsif verbose
+        outdated_info = token << " (#{outdated_versions(greedy).join(", ")})"
+        "#{outdated_info} != #{version}"
+      else
+        token
+      end
+    end
+
     def to_s
       @token
     end