Add `Highlight::reverse`

[zhiburt]

Nowadays Hightlight works from top to bottom and left to right, but it would be helpful if we could reverse it.

See.

use tabled::{
    builder::Builder,
    settings::{object::{Columns, Object, Rows}, themes::BorderCorrection, Border, Highlight, Span, Style}, Table,
};

fn main() {
    let mut builder: Builder = Builder::new();
    builder.push_record(vec!["", "a", "b", "c"]);
    builder.push_record(vec!["1", "", "", ""]);
    builder.push_record(vec!["2", "", "x", ""]);
    builder.push_record(vec!["3", "", "", ""]);

    let mut table = builder.build();
    table.with(Style::modern());
    table.modify((2, 2), (Span::column(2), Span::row(2)));
    table.with(BorderCorrection::span());
    table.with(Highlight::new(Columns::new(2..).intersect(Rows::new(2..))).border(Border::inherit(Style::modern())));

    println!("{table}");
}

┌───┬───┬───┬───┐
│   │ a │ b │ c │
├───┼───┼───┼───┤
│ 1 │   │   │   │
├───┼───┌───────┐
│ 2 │   │ x     │
├───┼───│       │
│ 3 │   │       │
└───┴───└───────┘

Reverse logic would do

┌───┬───┬───┬───┐
│   │ a │ b │ c │
├───┼───┼───┼───┤
│ 1 │   │   │   │
├───┼───┼───┴───┘
│ 2 │   │ x     │
├───┼───┤       │
│ 3 │   │       │
└───┴───┘───────┘

ref: #544

[zhiburt]

Or maybe a new setting for such a feature must be added.
But I feel like it belongs to Highlight

[hilcode]

The idea being that it would then be easier to remove the bottom right corner (of the combined 2x2 there)?

[zhiburt]

Regarding my example from #544.
It would greatly simplify it to the next snippet.

fn table_cleanup(t: &mut Table, pos: Position) {
    let cells = Rows::new(pos.row..).intersect(Columns::new(pos.col..));
    t.modify(cells.clone(), Border::filled(' '));

// See here we need a reverse logic.
    t.with(Highlight::new(cells).border(Border::inherit(Style::modern())));
}

So with .reverse() call we would get the next one.

┌───┬───┬───┬───┐
│   │ a │ b │ c │
├───┼───┼───┼───┤
│ 1 │   │   │   │
├───┼───┼───┴───┘
│ 2 │   │     
├───┼───┤
│ 3 │   │       
└───┴───┘

We sort of get this with Object::inverse.
But see it's just a little different.

┌───────────────┐
│   │ a │ b │ c │
│───┼───┼───┼───│
│ 1 │   │   │   │
│───┼───┌───────┘
│ 2 │   │ x      
│───┼───│        
│ 3 │   │        
└───────┘        

[hilcode]

Your code does not seem to use this new .reverse() method, though?

I think I get the idea, though. You want to indicate that certain cells should be treated as if they don't exist? That would seem like an elegant, relatively simple solution.