bug#33567: Syntactic fontification of diff hunks

[Juri Linkov]

>> What do you think about this solution that combines both
>> green/red foreground colors with syntax colors:
>>
>> https://gist.github.com/skanev/0eeb943e3111a1df55fd
>
> This is almost the look I complained about previously, but if the green and
> red are not as sharp, I suppose it's not too terrible. At least the lighter
> red doesn't scream "errors" to me.
>
> But note that this example does not show any "refined" functionality.

There are some underlines on this screenshot, maybe use underlines for
refined diffs on tty?