Update --cache command for generalized bottle implementation

Library/Homebrew/cmd/--cache.rb

@@ -1,9 +1,17 @@
+require "cmd/fetch"
+
 module Homebrew extend self
   def __cache
     if ARGV.named.empty?
       puts HOMEBREW_CACHE
     else
-      puts ARGV.formulae.map{ |f| f.cached_download }
+      ARGV.formulae.each do |f|
+        if fetch_bottle?(f)
+          puts f.bottle.cached_download
+        else
+          puts f.cached_download
+        end
+      end
     end
   end
 end