Revert r42938 "* lib/rubygems: Update to RubyGems 2.1.3"

It breaks build.
20130913T200302Z.diff.html.gz

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42941 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/rubygems/commands/check_command.rb

@@ -79,6 +79,13 @@ class Gem::Commands::CheckCommand < Gem::Command
     '--gems --alien'
   end
 
+  def description # :nodoc:
+    <<-EOF
+The check command can list and repair problems with installed gems and
+specifications and will clean up gems that have been partially uninstalled.
+    EOF
+  end
+
   def usage # :nodoc:
     "#{program_name} [OPTIONS] [GEMNAME ...]"
   end