Autosave

[maks]

Implements auto save functionality where project data file is autosaved every X period (currently 2min) to a backup file within the project directory. Note that autosaves will not occur while the sequencer is running but that time is taken into account, so autosave will then usually trigger immediately after sequencer is stopped.

This autosave data file is deleted each time there is an explicit project save operation done by the user. Thus when a project is loaded, if an autosave data file exists, it means it supercedes the last explicit save to the project data file and so the autosave file should be loaded in preference to it.

I also took the opportunity to update docs with initial explanations about the mainloop and clock tick event handling.

Fixes: #371

[democloid]

Code looks good, but to me there is a big gap in potential intent of what the user might want to do here and may be problematic.

If I load a file and mess around, an autosave happens, then I'm fucked, no way to scrap the changes.

To me there are three things that are important:

1. If the file was loaded from autosave, it needs to be explicitly be noted in the name of the project when loaded
2. If I save my project and no changes happen after that, then autosave should not happen (otherwise file will be marked as loaded from autosave when the last time I used it I saved and didn't change anything else)
3. If I explicitly load the project, it should load from my saved file. (I save before messing around with the project and testing some things, but then want to go back to my saved version)

In essence the way this is working today is that there is no difference between autosaved file and explicitly saved, since we cannot choose one or the other. If you autosaved to the normal save file functionality would be the same.

[maks]

Ok, as discussed offline: an explicit project load via the project screen will now load the last explicitly saved project data (lgptsav.dat) while onboot the last autosave file will be loaded unless its not available, in which case the project data file will be loaded.

The user manual has also been updated to explain the new autosave functionality from a users point of view.

[democloid]

Sorry, but I cannot see where the changes are to being able to load the saved project as opposed to the autosave file. Am I missing it?

It seems the load function will always load the autosave file if it exists.

[maks]

Sorry, but I cannot see where the changes are to being able to load the saved project as opposed to the autosave file. Am I missing it?

It seems the load function will always load the autosave file if it exists.

it works by removing the autosave just before rebooting to load the project (calling ClearAutoSave())