Temporarily show DONE entries in timeblock

[Gleek]

Adds a function to temporarily show DONE entries in timeblock.

This is more of a feature request with a patch.

Sometimes it's useful to view previous DONE entries as well. For example, while reviewing your life for previous day(s).

This works by setting up another property done with either y or n while setting things up in cache. This property is referred to again while generating the entries.

I've also added a small utility function and given it a keybind (a) that temporarily enables the done keyword and redraws the timeblock. Pressing g again to re-render would remove these DONE entries.

This is still very rough and might need some more thinking around it's UX. Maybe we can build further on top of this.

Regards.

PS: Thank you for sharing this package. I've looked for something like this for very long and I'm slightly disappointed that I've heard about it just now.