adds support for a series of slashes as path

Author: fxn

lib/action_controller/caching/pages.rb

@@ -141,7 +141,7 @@ def default_extension
           end
 
           def cache_file(path, extension)
-            if path.empty? || path == "/"
+            if path.empty? || path =~ %r{\A/+\z}
               name = "/index"
             else
               name = URI.parser.unescape(path.chomp("/"))