Allow using query parameters via the "target" key

[clau-bucur]

Allow using query parameters via the "target" key
Make "buffered" optional
Add some logging info

[clau-bucur]

This allows to execute commands which are easier to maintain or extend.
An example:

- service: notify.mysql_command
  data:
    message: >
      DELETE sst FROM statistics_short_term sst INNER JOIN statistics_meta sm ON sm.id = sst.metadata_id WHERE DATEDIFF(CURDATE(), FROM_UNIXTIME(sst.created_ts)) > %s
      AND
      (
        sm.statistic_id LIKE %s
        OR sm.statistic_id LIKE %s
        OR sm.statistic_id LIKE %s
        OR sm.statistic_id LIKE %s
        OR sm.statistic_id IN (%s, %s, %s)
      )
    target:
      [
        90,
        'sensor.thermal_comfort_outside_%',
        'sensor.average_%_cpu_nuc',
        'sensor.history_%washer_cycles',
        'sensor.history_tv_%',
        'sensor.history_heating_shower',
        'sensor.history_heating_hot_water',
        'sensor.history_heating_hot_water_hourly',
      ]