Update racc.en.rhtml

Updated instructions how to use latest version

doc/en/racc.en.rhtml

@@ -30,13 +30,11 @@ If you want to run your parsers with ruby 1.6.x,
 use "racc -E" command.  For details, see <a href="doc/">online manual</a>.
 </p>
 
-<h2>Anonymous CVS</h2>
+<h2>Git</h2>
 <p>
-You can true latest version of Racc via anonymous CVS.
-To check out working copy, type:
+You can use the latest version of Racc using git.
+To clone out a working copy, type:
 </p>
 <pre>
-$ cvs -d :pserver:anonymous@cvs.loveruby.net:/src login
-Password: (Just hit [Enter])
-$ cvs -d :pserver:anonymous@cvs.loveruby.net:/src co racc
+$ git clone https://github.com/ruby/racc.git
 </pre>