Store log file in the database and make it accessible in the Background Service History Viewer

Feature

• Currently it is not possible to show a log file for a transfer in the SOSFtp-GUI. If a transfer leads to an error then it the log file should be stored in the database.
• This includes to implement the functionality to retrieve the logs online (e.g. as the functionality used in JobScheduler).
• It should be possible to store
  1. all logs
  2. only logs from failed transfers
• The behavior for failed transfers should be custimizable with the client options.

Maintainer Notes

• We tend to dismiss this proposal as
  • there are better tools available for storing logs (log server tools)
  • a database is not the perfect location for a log
  • The functionality of logs being stored persistently is available with JobScheduler