Update readme for usage

README.md

@@ -11,7 +11,11 @@ Any pre-requisites that may not be covered by Ansible itself or the role should
 Role Variables
 --------------
 
-* main variable of type list
+* Lets Encrypt configuration
+  * lets_encrypt_admin : The Email address your Lets Encrypt account is with
+  * lets_encrypt_url : The ACME URL to speak with, defaults to Lets Encrypt, may set to 'https://acme-staging-v02.api.letsencrypt.org/directory' for Staging
+
+* Web Host variable of type list
   * http_vhost
 * required dictionary elements
   * fqdn : The FQDN of the website
@@ -20,6 +24,8 @@ Role Variables
   * proxy : URL to direct traffic for the FQDN to, e.g. http://localhost:8080
 
 ~~~
+lets_encrypt_admin: 'acme@example.com'
+lets_encrypt_url: 'https://ipa.example.com'
 http_vhost:
   - fqdn: 'www.example.com'
     aliases: