It would be great to have the ability to aggregate all log records in a single log file. As a short term solution, we could expose a new option to control FileOutputStream append, as a long term - design simple log retention functionality.

`org.slf4j.simpleLogger.logFileAppend`
When true, records will be appended to the end of the file. When set to false, the file will be cleared before new records are written. Defaults to `false` for backward compatibility.