// TODO

• Saving

We should be able to save project in the following ways:

• By Menu: File->Save
• By Shortcut: Ctrl+S (default)

Requirements

• If a project has just been created, then a dialog should open for choosing a name and a place where to save
• If project was saved earlier, then the changes should be written to the current file
• Each time we save, a backup file should be created containing the previous data.
• Using File->Save as..., we can save the project with a new file name, it becomes the current one. The old project file should remain unchanged.

// TODO