decode_credentials

# File actionpack/lib/action_controller/metal/http_authentication.rb, line 220
      def decode_credentials(header)
        header.to_s.gsub(/^Digest\s+/,'').split(',').inject({}) do |hash, pair|
          key, value = pair.split('=', 2)
          hash[key.strip.to_sym] = value.to_s.gsub(/^"|"$/,'').gsub(/'/, '')
          hash
        end
      end