DPE-5355 Ensure logs flushes

[paulomach]

Issue

Uncertain race/failure conditions can render a case where logs are being written to rotate file, i.e. the log file being written is under the archive_<log> directory.
Logrotate needs to match filename under the default directory to rotate AND flush the files.
This renders log rotation useless.

Solution

• ensure file exist before rotation by touching it
• refactor for dynamic generating log rotation configuration
  • reacts to changes in configuration
• renamed slow query to align with mysql naming
• removed slow query from rotation list, since it's disable by default

Fixes #523

[taurus-forever]

Great simplification!