Add option to extension's settings: "Preserve indentation on empty line"

[kyklish]

Changes proposed in this pull request:

• preserve indentation on empty line

foo() {
    bar()
[4 spaces]
    return
}

---

Notifying @mark-wiemer

[kyklish]

This PR depends on #164 PR, I need new functions from that PR to write unit test for this PR. Waiting for #164 review.

[kyklish]

If I cherrypick commit from another branch, will it make merge conflict for this branch (when another branch already merged to main)?

[mark-wiemer]

If I cherrypick commit from another branch, will it make merge conflict for this branch (when another branch already merged to main)?

Probably not, but I'm not sure. I'd assume it would minimize the chance of merge conflicts. Merge conflicts are caused by differences between the incoming branch (kyklish:option-preserve-indent-on-empty-line) and the base branch (main) changing the same parts of a file in different ways since the last commit common to both branches. If you cherry-pick from main and preserve the changes in that cherry-pick as-is, they shouldn't introduce merge changes, no. Because the changes in that commit will change the same parts of the files in the same way, so there's no difference that needs to be reconciled.

So I'd recommend using cherry-pick whenever possible :)