Release 0.9.0

Features:
- Add `mysql::backup::backuprotate` parameter
- Add `mysql::backup::delete_before_dump` parameter
- Add `max_user_connections` attribute to `database_user` type

Bugfixes:
- Add client package dependency for `mysql::db`
- Remove duplicate `expire_logs_days` and `max_binlog_size` settings
- Make root's `.my.cnf` file path dynamic
- Update pidfile path for Suse variants
- Fixes for lint
Merge pull request #225 from hunner/release_0.9.0

Release 0.9.0