L10n Update

• Localization support
  • German
  • French (Issue #51)
    • Thank you rei-vilo!
  • Korean (Issue #64)
    • Thank you Pusnow!
• removed advanced preference to allow the display to sleep (didn't work properly and lead to confusion)
  • the info.marcel-dierkes.KeepingYouAwake.AllowDisplaySleep preference was removed
  • a similar, more powerful replacement feature will be introduced soon