Suggestion: use list of indices instead of list of ranks

[jabcross]

Use case: a book club using this to decide what the next book will be.

We thought that the most intuitive ballot format should be a list of indices, ordered from highest to lowest priority.

When trying to decide, we don't know the rank of every option ahead of time. Instead, we manually sort our choices by swapping numbers around. We can't do that in the current list of ranks format without changing all of the ranks in-between the swaps, and we have to remember the position in the list that corresponds to each option, sometimes having to count commas.

This also would allow us to keep the same list of options between voting sessions, just adding options to the end. This would keep each book's index constant and allow us just to update the old ballots when considering a new book.