Remove mention of CentOS 7 in readme.

Author: geerlingguy

README.md

@@ -180,29 +180,6 @@ mysql_hide_passwords: false
 
 Do you need to hide tasks' output which contain passwords during the execution ?
 
-### Later versions of MySQL on CentOS 7
-
-If you want to install MySQL from the official repository instead of installing the system default MariaDB equivalents, you can add the following `pre_tasks` task in your playbook:
-
-```yaml
-  pre_tasks:
-    - name: Install the MySQL repo.
-      yum:
-        name: http://repo.mysql.com/mysql-community-release-el7-5.noarch.rpm
-        state: present
-      when: ansible_os_family == "RedHat"
-
-    - name: Override variables for MySQL (RedHat).
-      set_fact:
-        mysql_daemon: mysqld
-        mysql_packages: ['mysql-server']
-        mysql_log_error: /var/log/mysqld.err
-        mysql_syslog_tag: mysqld
-        mysql_pid_file: /var/run/mysqld/mysqld.pid
-        mysql_socket: /var/lib/mysql/mysql.sock
-      when: ansible_os_family == "RedHat"
-```
-
 ### MariaDB usage
 
 This role works with either MySQL or a compatible version of MariaDB. On RHEL/CentOS 7+, the mariadb database engine was substituted as the default MySQL replacement package. No modifications are necessary though all of the variables still reference 'mysql' instead of mariadb.

meta/main.yml

@@ -7,7 +7,7 @@ galaxy_info:
   description: MySQL server for RHEL/CentOS and Debian/Ubuntu.
   company: "Midwestern Mac, LLC"
   license: "license (BSD, MIT)"
-  min_ansible_version: 2.10
+  min_ansible_version: 2.12
   platforms:
     - name: Ubuntu
       versions: