Update README.md

Author: geografa

README.md

@@ -61,7 +61,7 @@ $ echo 'export PATH=/usr/local/opt/ruby/bin:$PATH' >> ~/.bash_profile
 Run the following in terminal:
 
  ```
-$ gem install jekyll -v 1.4.3
+$ gem install jekyll -v 2.4.0
 $ gem install rdiscount
  ```