Highlight lines related to the current lines commit

[Sertion]

Maybe we can use setDecorations to highlight lines related to the current lines commit. Add it behind a setting that is disabled by default.

It has been requested for a long time.

[Sertion]

I have done some work here, but I can't find a style that looks even close to good.

[Sertion]

There is a branch with the functionality started.

Only two things left:

• Figure out styling
• Add a setting to disable it

[Sertion]

With the new design for the info boxes this will be even harder to figure out. If this is wanted by anybody and they are willing to build it, please feel free to create a pull request in the future. Until then this issue is closed.