vim:plugs: Add vim-sort-folds

> Sorting folds is not easily possible in vanilla vim. You could join
> all lines in a fold, sort and split them up again; however, it is time
> consuming and tedious.
>
> This little plugin solves that issue: It sorts a visually selected
> region while keeping closed folds intact. Since folds can be created
> in a variety of ways, it is therefore straight-forward to sort
> arbitrary groups of text based on their first line.

.config/vim/pack/plugins/start/vim-sort-folds

@@ -0,0 +1 @@
+../opt/vim-sort-folds/