add proxysql_version as default variable

Bump ansible from 2.8.5 to 2.8.8

Bump psutil from 5.6.3 to 5.6.6

Enable proxysql service

Bumps [psutil](https://github.com/giampaolo/psutil) from 5.6.3 to 5.6.6.
- [Release notes](https://github.com/giampaolo/psutil/releases)
- [Changelog](https://github.com/giampaolo/psutil/blob/master/HISTORY.rst)
- [Commits](https://github.com/giampaolo/psutil/compare/release-5.6.3...release-5.6.6

)

Signed-off-by: dependabot[bot] <support@github.com>

Bumps [ansible](https://github.com/ansible/ansible) from 2.8.5 to 2.8.8.
- [Release notes](https://github.com/ansible/ansible/releases)
- [Commits](https://github.com/ansible/ansible/compare/v2.8.5...v2.8.8

)

Signed-off-by: dependabot[bot] <support@github.com>

Logrotate Flush + Tests :

- Adding logrotate /var/lib/logrotate
- Adding Flush LOGS before logrotating ;
- Changed ubuntu to vagrant user for tests ;
- Adding mysql test table assert ;

Added new variables
- proxysql_mysql_server_version (fixes #3)
- basic cluster support (proxysql_cluster_name & proxysql_cluster_password)

Added hot reloading for configuration changes (proxysql does not pick them up unless we use --initial). Fixes #2

Added molecule testing support

Fixed proxysql typo in config

Removes proxysql_version variable.
This implies version 1.4.2+ is used if cluster is set up

Switched from download install to precona repositories

Separated upstream mysql config from proxylsql mysql config

Added proxysql_mysql_servers_group which allows invenroty group reuse in
config generation

Added 1.4.2+ clustering support

Wrong variable was being used in template.
Spotted by @aavileli . Thanks.

Added configuration for logrotate

Added missing meta file

Long time no see, just checking

Added note on ansible compat