v0.6.0
  - possibilty to copy tasks and variables
  - redesigned/improved ui and validation behavior of all dialog windows
  - fallback icons removal
  - fix to crontablib parser
  - minor fixes and improvements

 v0.5.0
  - PolKit authorization via KAuth, root actions
  - filtering items in the main window
  - minor fixes and improvements

 v0.4.0
  - codebase rewritten in C++14 standard, code simplified
  - dialog windows were sligthly redesigned and improved
  - fix for the issue with excessive quoting of Command and Timer entries
  - workaround for KDE bug when the icon text is not being set
  - minor fixes and improvements