Full buster optim (#38)

* Remove Stretch and Percona support
* Delete root password management (On Buster, it uses socket auth)
* Fix sync backups files master -> slave
* Cleanup legacy code on replication slave
* Use modern configuration
* Debian buster configuration style
* Drop logrotate management (useless)
* Add new default values in defaults/main.yml (according with MariaDB doc)
* Travis with Ansible 2.8+
* Drop feature "don't replicate mysql database"
* Fully compatible with python3

tasks/galera/main.yml

@@ -2,8 +2,8 @@
 
 - name: TEMPLATE | Deploy Galera configuration
   template:
-    src: etc/mysql/conf.d/09-galera.cnf.j2
-    dest: /etc/mysql/conf.d/09-galera.cnf
+    src: etc/mysql/mariadb.conf.d/20-galera.cnf.j2
+    dest: /etc/mysql/mariadb.conf.d/20-galera.cnf
   register: galeraconfig
 
 - name: INCLUDE | Bootstrap first node