README: Use --line-range instead of head in bat example

[xeruf]

From the bat man page:

       -r, --line-range <N:M>...

              Only print the specified range of lines for each file. For example:

              --line-range 30:40
                     prints lines 30 to 40

              --line-range :40
                     prints lines 1 to 40

I think this should be more efficient than head?
And either way, it is the proper way, better to make it easy to find because it took me some time to find it 😅

Also, why 500 lines? What insane terminal is that where you can see 500 lines vertically without scrolling? ^^

[junegunn]

500, which is an arbitrary number that is supposed to be larger than the height of a normal terminal, allows you to scroll down the preview window for some degree, while still limiting the number of lines fzf has to process. There is no particular reason that it should be 500, but 99 seems not enough, e.g. pivot screen.

[xeruf]

how can I scroll the preview?

[junegunn]

Using mouse scroll or using custom --bind keys.

[xeruf]

oh wow, I didn't even notice that - maybe add that to the README ;)

[xeruf]

alright, I set it back to 500

[xeruf]

and added a hint for scrolling

[junegunn]

Merged, thanks!