git.ruby-lang.org may be slow than github.com from oversea

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67676 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

README.md

@@ -56,7 +56,7 @@ to see the list of branches:
 
     $ git ls-remote https://github.com/ruby/ruby.git
 
-You may also want to use https://git.ruby-lang.org/ruby.git for better latency.
+You may also want to use https://git.ruby-lang.org/ruby.git for better latency in Japan.
 
 ## Ruby home page