Improve operational maintainability of KIM

[tobiscr]

Description

Challenge the current operational maintainability of KIM. Ensure the system is providing in logs sufficient and expressive information to allow simple analysis.

AC:

• Logging an error should also include stack traces
• Log levels have to be chosen properly and messages have to be expressive / self-explaining: it has always be possible to find the code place where the log was generated.
  • Debug = for development purposes, tracing
  • Info = Relevant information to reflect the current state of the system
  • Warn = Critical / unexpected situation occurred but could be handled by the system
  • Error = non-recoverable failure, engineer has to be reviewed

[tobiscr]

Duplicate of #388