PR geerlingguy#83 follow-up

Author: geerlingguy

README.md

@@ -18,10 +18,11 @@ Available variables are listed below, along with default values (see `defaults/m
 
 The repository to use when installing Apache (only used on RHEL/CentOS systems). If you'd like later versions of Apache than are available in the OS's core repositories, use a repository like EPEL (which can be installed with the `geerlingguy.repo-epel` role).
 
+    apache_listen_ip: "*"
     apache_listen_port: 80
     apache_listen_port_ssl: 443
 
-The ports on which apache should be listening. Useful if you have another service (like a reverse proxy) listening on port 80 or 443 and need to change the defaults.
+The IP address and ports on which apache should be listening. Useful if you have another service (like a reverse proxy) listening on port 80 or 443 and need to change the defaults.
 
     apache_create_vhosts: true
     apache_vhosts_filename: "vhosts.conf"