Twenties: refactor to use the scheduling library instead of its own timeouts

[thyttan]

Work in progress.

Try the current iteration at: https://thyttan.github.io/BangleApps/?id=twenties

[elfehr]

Thanks for working on that!
Maybe you could add msg: "Twenties" to the alarm, to make it clear where it comes from so users are less likely to delete it? I wonder if there is a way to hide it completely or make it undeletable. Or maybe recreating it on boot if it has been deleted?

For curiosity, how are you testing the code in the IDE? On my side, it doesn't read the file from storage correctly, and if I upload the unminified javascript (either to RAM or to storage, replacing the original), I have an error that sched is not found and exports is not defined.

[thyttan]

if I upload the unminified javascript (either to RAM or to storage, replacing the original), I have an error that sched is not found and exports is not defined.

I get those as well, but it works anyways. When the code runs on the watch it will find the sched library file and use it (if you installed it before). But it's probably good to get that error when uploading so you know to get the library if you haven't already.

The exports not being defined is similar in that when running on the watch it will work. Maybe the Web IDE should be made to not fire that error? @gfwilliams

[thyttan]

I wonder if there is a way to hide it completely or make it undeletable.

Yes I think that makes sense. Gordon and I discussed it some in #4217

Or maybe recreating it on boot if it has been deleted?

I did that before. I prefer to avoid it. But maybe it makes sense.