Feature request: mark sections of page a read.

[andrewcrook]

example: add read from and to markers and colour the in-between to so that parts of a page has been read.

It should be possible to to workout the sections read as a percentage of the page length Therefore, could be integrated into #239 feature request for adding progress reading.

[fonol]

Personally, I am okay atm with marking the page as read when I reached the end of it. Of course it would be more precise to mark the exact position, but I don't really feel the need for it, and it sounds like quite some work for what is essentially only a small quality of life improvement.

[andrewcrook]

@finol

The issue is if you are using PDF as a references you don't tend to read all of it and in order. However, it might be useful if you later come back to the book, to read sections for a different class or just to complete a chapter, section or the rest of the book etc at a later date.