Add basic support for delaying and combining text changes (#262)

[strpbrk]

I have managed to implement it with minimal impact on dependencies, and should work correctly up to the latest dependencies.

[HighCommander4]

@strpbrk just to confirm my understanding, this patch has the issues described in this comment, and is thus not suitable to be reviewed and merged in its current form, right?

[strpbrk]

@HighCommander4 it has at least those issues. More issues may have been introduced with API changes over the years, which I have not tracked. If I ever make time to get back to this problem, I will make a new evaluation, bug reports, pulls, etc.

[HighCommander4]

@HighCommander4 it has at least those issues. More issues may have been introduced with API changes over the years, which I have not tracked. If I ever make time to get back to this problem, I will make a new evaluation, bug reports, pulls, etc.

Thanks. I've marked this PR as a "draft" to make it clear that it's not ready for review.