and WEBrick::CGI#config.  these are necessary to use an instance of
  WEBrick::CGI as the first argument of HTTPServlet#get_instance.
  (suggested by Tatsuki Sugiura)

* lib/webrick/cgi.rb
  (WEBrick::CGI#initalize): set a dummy to @config[:ServerSoftware]
  if SERVER_SOFTWARE environment variable is not given.
  (WEBrick::CGI#start): req.path_info must be a String.
  (WEBrick::CGI::Socket#request_line): treat REQUEST_METHOD, PATH_INFO
  and SCRIPT_NAME to run in console.

* lib/webrick/httputils.rb (WEBrick::HTTPUtils.escape_path): should
  not use String#split("/"). it removes trailing empty path component.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@8393 b2dd03c8-39d4-4d8f-98ff-823fe69b080e