Add link to CentOS 5 tutorial

README.md

@@ -12,7 +12,7 @@ This tool simplifies the manual process of using LetsEncrypt on Webfaction hosts
 
 ## Installation
 
-This utility works on [CentOS 6 and 7 boxes](https://docs.webfaction.com/user-guide/server.html#finding-your-server-s-operating-system). The CentOS 5 systems do not have a new enough OpenSSL to include the algorithms required. You may be able to make this work using rbenv and compiling openssl yourself.
+This utility works on [CentOS 6 and 7 boxes](https://docs.webfaction.com/user-guide/server.html#finding-your-server-s-operating-system). The CentOS 5 systems do not have a new enough OpenSSL to include the algorithms required. You may be able to make this work using rbenv and compiling openssl yourself. A tutorial for CentOS 5 is available here: https://github.com/will-in-wi/letsencrypt-webfaction/wiki/Install-custom-OpenSSL-and-Ruby-on-CentOS-5-host
 
 You can install LetsEncrypt Webfaction using the system Ruby or using RBEnv.