adapted README to cover install from package possibility

README.md

@@ -6,26 +6,27 @@ Installs Certbot (for Let's Encrypt) for RHEL/CentOS or Debian/Ubuntu.
 
 ## Requirements
 
-Certbot requires Git to be installed. You can install Git using the `geerlingguy.git` role.
+Certbot requires Git to be installed if one wants to install Certbot from Git repository instead of package management. You can install Git using the `geerlingguy.git` role.
 
 ## Role Variables
 
+    certbot_from_git: no
     certbot_repo: https://github.com/certbot/certbot.git
     certbot_version: master
     certbot_keep_updated: yes
 
-Certbot code repository options. This role clones the agent from the configured repo, then makes the `certbot-auto` script executable.
+Certbot Git repository options. This role clones the agent from the configured repo, then makes the `certbot-auto` script executable if `certbot_from_git` is `yes`. Otherwise it will be installed from distribution's package management.
 
     certbot_dir: /opt/certbot
 
-The directory inside which Certbot will be cloned.
+The directory inside which Certbot will be cloned when using Git.
 
     certbot_auto_renew: true
     certbot_auto_renew_user: "{{ ansible_user }}"
     certbot_auto_renew_hour: 3
     certbot_auto_renew_minute: 30
 
-By default, this role configures a cron job to run under the provided user account at the given hour and minute, every day. The defaults run `certbot-auto renew` via cron every day at 03:30:00 by the user you use in your Ansible playbook. It's preferred that you set a custom user/hour/minute so the renewal is during a low-traffic period and done by a non-root user account.
+By default, this role configures a cron job to run under the provided user account at the given hour and minute, every day. The defaults run `certbot renew` (or `certbot-auto renew`) via cron every day at 03:30:00 by the user you use in your Ansible playbook. It's preferred that you set a custom user/hour/minute so the renewal is during a low-traffic period and done by a non-root user account.
 
 ## Dependencies
 
@@ -43,7 +44,7 @@ None.
       roles:
         - geerlingguy.certbot
 
-After installation, you can create certificates using the `certbot-auto` script, which by default is installed inside the configured `certbot_dir`, so by default, `/opt/certbot/certbot-auto`. Here are some example commands to configure certificates with Certbot:
+After installation, you can create certificates using the `certbot` (or `certbot-auto`) script, which by default is installed inside the configured `certbot_dir` (when using Git). Here are some example commands to configure certificates with Certbot:
 
     # Automatically add certs for all Apache virtualhosts (use with caution!).
     /opt/certbot/certbot-auto --apache