- adding undo/redo buttons to the header bar, removing from context menu
- moving
Saveto application menu - adding
Open...andSaveto application menu - refactoring: move some action definitions from application to window context
- adding undo/redo buttons to the header bar, removing from context menu
- moving `Save` to application menu
- adding `Open...` and `Save` to application menu
- refactoring: move some action definitions from application to window context
Related: #106, #123