Tweak the Ruby 2.0 note

README.md

@@ -92,14 +92,16 @@ To see a list of all available Ruby versions, run `ruby-build
 Pass the `-v` or `--verbose` flag to `ruby-build` as the first
 argument to see what's happening under the hood.
 
-Ruby 2 is incompatible with the version of OpenSSL bundled with Mac OS X, so it
-doesn't compile the extension.
+### A note about Ruby 2.0 and Mac OS X
 
-To work around this issue, install OpenSSL using homebrew instead:
+Ruby 2.0 is incompatible with the version of OpenSSL bundled with Mac
+OS X. To work around this issue, install OpenSSL using Homebrew
+instead:
 
     brew install openssl
 
-Then set the CONFIGURE_OPTS environment variable when you build Ruby:
+Then set the `CONFIGURE_OPTS` environment variable when you build
+Ruby:
 
     CONFIGURE_OPTS=--with-openssl-dir=`brew --prefix openssl` rbenv install 2.0.0-preview1