Test cases:
  fd --color always | fzf --ansi --delimiter /
  fd --color always | fzf --ansi --delimiter / --nth -1 --color fg:dim,nth:regular
  fd --color always | fzf --ansi --delimiter / --nth -1 --color fg:dim:strip,nth:regular
  fd --color always | fzf --ansi --delimiter / --nth -1 --color fg:dim:strip,nth:regular --raw
  fd --color always | fzf --ansi --delimiter / --nth -1 --color fg:dim:strip,nth:regular,hidden:strikethrough --raw
  fd --color always | fzf --ansi --delimiter / --nth -1 --color fg:dim:strip,nth:regular,hidden:strip:strikethrough --raw
  fd --color always | fzf --ansi --delimiter / --nth -1 --color fg:dim:strip,nth:regular,hidden:strip:dim:strikethrough --raw

Example:
  # foo was not displayed in italic
  echo -e "\x1b[33;3mfoo \x1b[mbar" | fzf --ansi --color fg:dim,nth:regular --nth 1

Test cases:

1. 'jump' should show alternating background colors even when 'alt-bg' is
not defined as before.

  go run main.go --bind load:jump

Two differences:
  * The alternating lines will not be in bold (was a bug)
  * The marker column will not be rendered with alternating background color

2. Use alternating background color when 'alt-bg' is set

  go run main.go --color bg:238,alt-bg:237
  go run main.go --color bg:238,alt-bg:237 --highlight-line

3. 'selected-bg' should take precedence

  go run main.go --color bg:238,alt-bg:237,selected-bg:232 \
                 --highlight-line --multi --bind 'load:select+up+select+up'

4. Should work with text with ANSI colors

  declare -f | perl -0777 -pe 's/^}\n/}\0/gm' |
    bat --plain --language bash --color always |
    go run main.go --read0 --ansi --reverse --multi \
                   --color bg:237,alt-bg:238,current-bg:236 --highlight-line

---

Close #4354
Fix #4372

Close #4183

Close #2165

Fix #3596

Favors the line with shorter matched chunk. A chunk is a set of
consecutive non-whitespace characters.

Unlike the default `length`, this new scheme works well with tabular input.

  # length prefers item #1, because the whole line is shorter,
  # chunk prefers item #2, because the matched chunk ("foo") is shorter
  fzf --height=6 --header-lines=2 --tiebreak=chunk --reverse --query=fo << "EOF"
  N | Field1 | Field2 | Field3
  - | ------ | ------ | ------
  1 | hello  | foobar | baz
  2 | world  | foo    | bazbaz
  EOF

If the input does not contain any spaces, `chunk` is equivalent to
`length`. But we're not going to set it as the default because it is
computationally more expensive.

Close #2285
Close #2537
- Not the exact solution to --tiebreak=length not taking --nth into account,
  but this should work. And the added benefit is that it works well even
  when --nth is not provided.
- Adding a bonus point to the last character of a word didn't turn out great.
  The order of the result suddenly changes when you type in the last
  character in the word producing a jarring effect.