Complete holiday dialog interface
Debug, compile, install ...
Fix shortcut
Add main window size hint
Implement basic holiday creation
Fixes
Fix order of names, standardize colors
Highlight hovered holidays
Handle clicks on holidays
Create context menu
Fixup
Require double click for a new entry
Different colors for different types
Force start date before end date
Allow choosing holiday types
Add window icon
Create dummy icon
Use icon for shortcut
Add delete button
Require confirmation before deletion