Autosave

[BigBahss]

Adds an auto-save feature which is configured in the PreferenceEditor. Auto-save can be set up to save a map after a set delay, when changing maps, or both. Auto-save doesn't create any temporary files, it saves directly to the project files. Due to this, there is a prominent warning in the preferences not to enable auto-save if the user is not using git.

[BigBahss]

One limitation is that the "Auto-Save Delay" option depends on the undo history to track changes to maps. Since not every single type of edit is hooked into the undo history, the auto-save timer will not detect those changes (but those edits will be saved when auto-save does detect an edit).

[huderlem]

Closing this for now. Will maybe revisit autosave in the future.